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TDMS Study 05075-02 Pathology Tables


                                     INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)
                                                         DIPHENYLHYDANTOIN


NTP Experiment-Test: 05075-02                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 09/09/94
Route: DOSED FEED                                                                                                 Time: 15:41:56




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  57-41-0

       Lock Date:  None

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All
































a  Number of animals examined microscopically at site and number of animals with lesion

                                                             Page   1

NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        0 PPM        60 PPM       200 PPM      200 PPM      200 PPM         
                                                    0-0          10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50           50           50           
  Early Deaths                                                                                                                      
    Natural Death                                      6            5            6            7            6            4           
    Moribund Sacrifice                                 8           11            9            6            6            8           
  Survivors                                                                                                                         
    Terminal Sacrifice                                36           34           35           37           38           38           
  Animals Examined Microscopically                    50           50           50           50           50           50           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                             (46)         (15)         (20)         (13)         (10)         (11)         
      Fibrosis                                                                                                          1 (9%)      
      Parasite Metazoan                                                                                    1 (10%)                  
   Intestine Small, Duodenum                          (47)         (14)         (14)         (12)         (10)         (10)         
      Inflammation, Acute, Necrotizing                                           1 (7%)                    1 (10%)      2 (20%)     
   Intestine Small, Ileum                             (46)         (15)         (14)         (14)         (11)         (11)         
      Inflammation, Acute, Necrotizing                                                                                  1 (9%)      
   Intestine Small, Jejunum                           (48)         (16)         (14)         (15)         (12)         (11)         
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
   Liver                                              (48)         (49)         (50)         (50)         (50)         (49)         
      Basophilic Focus                                 1 (2%)       2 (4%)                    3 (6%)       2 (4%)       1 (2%)      
      Clear Cell Focus                                 1 (2%)                                                           1 (2%)      
      Degeneration, Cystic                                                                    1 (2%)                    1 (2%)      
      Eosinophilic Focus                                            1 (2%)       3 (6%)       5 (10%)      4 (8%)       3 (6%)      
      Fatty Change                                     2 (4%)                    6 (12%)     26 (52%)     27 (54%)     23 (47%)     
      Hematopoietic Cell Proliferation                 2 (4%)                    2 (4%)                    1 (2%)       1 (2%)      
      Infarct, Multifocal                              6 (13%)      5 (10%)      3 (6%)       2 (4%)       2 (4%)       3 (6%)      
      Infiltration Cellular, Lymphocyte                             1 (2%)                                                          
      Inflammation, Chronic                                                                   5 (10%)      1 (2%)                   
      Mixed Cell Focus                                              1 (2%)                                                          
      Necrosis, Focal                                                            1 (2%)                                             
      Regeneration, Diffuse                            1 (2%)                                                                       
      Bile Duct, Hyperplasia                                                                                            1 (2%)      
      Centrilobular, Congestion, Chronic                                                      1 (2%)                                
      Centrilobular, Cytomegaly                                                  3 (6%)      26 (52%)     25 (50%)     25 (51%)     
      Hepatocyte, Necrosis                                                                    1 (2%)       1 (2%)                   
   Mesentery                                          (8)          (2)          (5)          (4)          (4)          (2)          
      Inflammation, Suppurative                                                  1 (20%)      1 (25%)      1 (25%)                  
      Artery, Inflammation, Chronic Active                                       1 (20%)      1 (25%)                               
      Fat, Necrosis                                    1 (13%)                   2 (40%)      1 (25%)      1 (25%)                  
   Pancreas                                           (47)         (15)         (15)         (12)         (12)         (11)         
      Inflammation, Chronic                                                      1 (7%)                                 1 (9%)      
      Acinus, Atrophy                                  6 (13%)                   2 (13%)                   2 (17%)      2 (18%)     
      Acinus, Focal Cellular Change                    1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        0 PPM        60 PPM       200 PPM      200 PPM      200 PPM         
                                                    0-0          10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Duct, Dilatation                                 1 (2%)                    1 (7%)                    1 (8%)                   
      Duct, Hyperplasia                                                                                                 1 (9%)      
   Salivary Glands                                    (49)         (15)         (14)         (14)         (12)         (11)         
      Necrosis                                                      1 (7%)                                                          
   Stomach, Forestomach                               (48)         (20)         (20)         (20)         (12)         (16)         
      Cyst                                                                       1 (5%)                    1 (8%)                   
      Hyperplasia, Squamous                                                                   4 (20%)                   3 (19%)     
      Epithelium, Hyperplasia                                                    2 (10%)      2 (10%)                   2 (13%)     
   Stomach, Glandular                                 (48)         (16)         (16)         (15)         (11)         (13)         
      Cyst                                                                       1 (6%)                                             
      Artery, Inflammation, Chronic Active                                                    1 (7%)                                
   Tooth                                              (5)                                    (1)                       (1)          
      Incisor, Upper, Dysplasia                        3 (60%)                                1 (100%)                  1 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (16)         (15)         (13)         (12)         (13)         
      Bacterium                                                                               1 (8%)                    1 (8%)      
      Cardiomyopathy, Chronic Active                   2 (4%)                                 1 (8%)                                
      Mineralization                                                1 (6%)                                                          
      Artery, Inflammation, Chronic Active                                       2 (13%)      2 (15%)                               
      Atrium, Thrombosis                                                                                                1 (8%)      
      Valve, Inflammation, Suppurative                                                                                  1 (8%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (48)         (16)         (14)         (13)         (12)         (11)         
      Hematopoietic Cell Proliferation                                                                     1 (8%)                   
      Hypertrophy                                      3 (6%)                                                                       
      Necrosis                                         1 (2%)                                                                       
      Corticomedullary Junction, Degeneration,                                                                                      
           Fatty                                       5 (10%)                                             1 (8%)                   
   Adrenal Gland, Medulla                             (48)         (16)         (14)         (13)         (12)         (11)         
      Hyperplasia                                      1 (2%)       1 (6%)                                              1 (9%)      
   Pituitary Gland                                    (44)         (19)         (17)         (17)         (14)         (15)         
      Pars Distalis, Hyperplasia                      19 (43%)                   1 (6%)       2 (12%)      1 (7%)       2 (13%)     
   Thyroid Gland                                      (47)         (16)         (15)         (14)         (12)         (11)         
      Inflammation, Chronic Active                     3 (6%)                                                                       
      Follicular Cell, Hyperplasia                     4 (9%)       1 (6%)                    1 (7%)       1 (8%)       2 (18%)     
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        0 PPM        60 PPM       200 PPM      200 PPM      200 PPM         
                                                    0-0          10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (1)                                    (1)                                    
      Duct, Dilatation                                 1 (100%)                               1 (100%)                              
   Ovary                                              (49)         (28)         (36)         (28)         (25)         (30)         
      Angiectasis                                      1 (2%)       1 (4%)                                              1 (3%)      
      Cyst                                            25 (51%)     17 (61%)     29 (81%)     16 (57%)     15 (60%)     24 (80%)     
      Fibrosis                                                                                                          1 (3%)      
      Inflammation, Chronic Active                                                            6 (21%)      2 (8%)       1 (3%)      
      Mineralization                                   1 (2%)                                                                       
      Thrombosis                                       2 (4%)                    1 (3%)                    1 (4%)       1 (3%)      
   Uterus                                             (49)         (36)         (31)         (33)         (33)         (32)         
      Dilatation                                                    2 (6%)       1 (3%)       1 (3%)       2 (6%)                   
      Fibrosis                                                                                                          1 (3%)      
      Inflammation, Chronic Active                                                            2 (6%)                                
      Inflammation, Suppurative                        1 (2%)                    2 (6%)       2 (6%)       3 (9%)       1 (3%)      
      Thrombosis                                                                                                        1 (3%)      
      Endometrium, Hyperplasia, Cystic                15 (31%)     18 (50%)     16 (52%)     20 (61%)     24 (73%)     25 (78%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (48)         (16)         (15)         (13)         (12)         (11)         
      Myelofibrosis                                    1 (2%)                                                                       
      Femoral, Myelofibrosis                           2 (4%)                                                           1 (9%)      
   Lymph Node                                         (50)         (18)         (16)         (20)         (15)         (20)         
      Lumbar, Edema                                                                           1 (5%)                                
      Mandibular, Edema                                                                       1 (5%)                    1 (5%)      
      Mandibular, Hyperplasia, Lymphoid                                                                                 1 (5%)      
      Mediastinal, Inflammation, Suppurative                                                               2 (13%)                  
      Pancreatic, Hyperplasia, Lymphoid                                                                                 1 (5%)      
   Lymph Node, Mesenteric                             (12)         (7)          (5)          (6)          (4)          (9)          
      Angiectasis                                      3 (25%)      2 (29%)      1 (20%)                                1 (11%)     
      Necrosis                                                      1 (14%)                                                         
   Spleen                                             (48)         (23)         (27)         (23)         (23)         (27)         
      Hematopoietic Cell Proliferation                 6 (13%)      1 (4%)       5 (19%)      4 (17%)      6 (26%)      3 (11%)     
      Hyperplasia, Lymphoid                                         2 (9%)       3 (11%)                   3 (13%)      2 (7%)      
      Necrosis                                                      1 (4%)                                                          
   Thymus                                             (42)         (12)         (11)         (9)          (11)         (10)         
      Necrosis                                         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        0 PPM        60 PPM       200 PPM      200 PPM      200 PPM         
                                                    0-0          10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (46)         (15)         (12)         (13)         (9)          (5)          
      Hyperplasia, Cystic                              1 (2%)                                                                       
   Skin                                               (49)         (16)         (17)         (13)         (12)         (13)         
      Inflammation, Chronic Active                     1 (2%)                                 1 (8%)                                
      Subcutaneous Tissue, Fibrosis                    1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (16)         (15)         (13)         (13)         (12)         
      Compression                                      1 (2%)       1 (6%)                                                          
      Hemorrhage                                       2 (4%)                                                                       
      Necrosis                                         1 (2%)                    1 (7%)                                             
      Artery, Inflammation, Chronic Active                                       1 (7%)                                             
      Meninges, Infiltration Cellular, Lymphocyte                                             1 (8%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (20)         (20)         (15)         (13)         (13)         
      Bacterium                                                                                                         1 (8%)      
      Hemorrhage, Chronic                                                                     1 (7%)                                
      Hyperplasia, Lymphoid                                                                                1 (8%)                   
      Inflammation, Acute                                                                                               1 (8%)      
      Inflammation, Chronic Active                     3 (6%)       2 (10%)                   3 (20%)      2 (15%)                  
      Alveolar Epithelium, Hyperplasia                 4 (8%)                    1 (5%)                                             
   Nose                                               (50)         (16)         (15)         (13)         (12)         (12)         
      Mucosa, Inflammation, Suppurative                1 (2%)                                                                       
      Nasolacrimal Duct, Inflammation, Suppurative                               1 (7%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (2)          (2)          (1)          (2)          (1)          (3)          
      Degeneration                                     2 (100%)                               2 (100%)     1 (100%)     3 (100%)    
      Cornea, Inflammation, Chronic Active                          2 (100%)                                                        
   Harderian Gland                                    (8)          (4)          (4)          (3)          (4)          (4)          
      Hyperplasia                                      3 (38%)                   1 (25%)      1 (33%)                               
      Inflammation, Chronic Active                     1 (13%)                                                                      
   Zymbal's Gland                                                                                                      (1)          
      Dilatation                                                                                                        1 (100%)    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        0 PPM        60 PPM       200 PPM      200 PPM      200 PPM         
                                                    0-0          10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (48)         (16)         (16)         (13)         (14)         (12)         
      Cyst                                                                       2 (13%)                                            
      Nephropathy, Chronic                            14 (29%)      4 (25%)                   4 (31%)      1 (7%)       1 (8%)      
      Artery, Inflammation, Chronic Active                                                    1 (8%)                                
      Glomerulus, Inflammation,                                                                                                     
          Membranoproliferative                        1 (2%)       1 (6%)                    1 (8%)                                
      Pelvis, Inflammation, Suppurative                                                       1 (8%)                                
      Renal Tubule, Necrosis                           1 (2%)                    1 (6%)       1 (8%)                                
      Renal Tubule, Regeneration                                                 1 (6%)                                             
   Urinary Bladder                                    (48)         (15)         (15)         (13)         (11)         (11)         
      Artery, Inflammation, Chronic Active                                                    1 (8%)       1 (9%)       1 (9%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        600 PPM      600 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50                                                               
  Early Deaths                                                                                                                      
    Natural Death                                      4            5                                                               
    Moribund Sacrifice                                 6            8                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                40           37                                                               
  Animals Examined Microscopically                    50           50                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)         (48)                                                             
      Parasite Metazoan                                             1 (2%)                                                          
   Intestine Small, Jejunum                           (48)         (48)                                                             
      Edema                                            1 (2%)                                                                       
      Inflammation, Acute, Necrotizing                 1 (2%)       1 (2%)                                                          
   Liver                                              (50)         (50)                                                             
      Basophilic Focus                                 3 (6%)       4 (8%)                                                          
      Clear Cell Focus                                 5 (10%)      1 (2%)                                                          
      Degeneration, Cystic                                          5 (10%)                                                         
      Eosinophilic Focus                               8 (16%)      8 (16%)                                                         
      Fibrosis, Multifocal                             1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 1 (2%)                                                                       
      Infarct, Multifocal                              6 (12%)     11 (22%)                                                         
      Inflammation, Chronic                                         2 (4%)                                                          
      Mixed Cell Focus                                 2 (4%)                                                                       
      Vacuolization Cytoplasmic                        1 (2%)                                                                       
      Centrilobular, Cytomegaly                       37 (74%)     31 (62%)                                                         
   Mesentery                                          (6)          (6)                                                              
      Artery, Inflammation, Chronic Active             1 (17%)                                                                      
   Pancreas                                           (49)         (48)                                                             
      Inflammation, Chronic                                         1 (2%)                                                          
      Acinus, Atrophy                                  5 (10%)      3 (6%)                                                          
      Acinus, Depletion Secretory                      1 (2%)       1 (2%)                                                          
      Artery, Inflammation, Chronic Active             2 (4%)                                                                       
   Stomach, Forestomach                               (49)         (48)                                                             
      Diverticulum                                     1 (2%)                                                                       
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Tooth                                              (12)         (9)                                                              
      Incisor, Upper, Dysplasia                       10 (83%)      7 (78%)                                                         
      Peridontal Tissue, Inflammation, Suppurative     1 (8%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        600 PPM      600 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)                                                             
      Artery, Inflammation, Chronic Active             2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (50)         (48)                                                             
      Hematopoietic Cell Proliferation                 1 (2%)       1 (2%)                                                          
      Hyperplasia                                                   1 (2%)                                                          
      Hypertrophy                                                   2 (4%)                                                          
      Thrombosis                                                    1 (2%)                                                          
   Adrenal Gland, Medulla                             (50)         (48)                                                             
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (44)         (41)                                                             
      Pars Distalis, Hyperplasia                      17 (39%)     17 (41%)                                                         
   Thyroid Gland                                      (49)         (50)                                                             
      Inflammation, Chronic Active                     4 (8%)                                                                       
      Follicular Cell, Hyperplasia                    15 (31%)     13 (26%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Ovary                                              (50)         (49)                                                             
      Angiectasis                                      2 (4%)       2 (4%)                                                          
      Cyst                                            13 (26%)     18 (37%)                                                         
      Thrombosis                                       1 (2%)       1 (2%)                                                          
   Uterus                                             (50)         (50)                                                             
      Dilatation                                       3 (6%)       3 (6%)                                                          
      Inflammation, Suppurative                        2 (4%)       1 (2%)                                                          
      Endometrium, Hyperplasia, Cystic                              8 (16%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (50)                                                             
      Femoral, Myelofibrosis                           2 (4%)       3 (6%)                                                          
   Lymph Node, Mesenteric                             (6)          (6)                                                              
      Angiectasis                                                   1 (17%)                                                         
      Hyperplasia, Lymphoid                                         1 (17%)                                                         
   Spleen                                             (50)         (48)                                                             
      Hematopoietic Cell Proliferation                              2 (4%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        600 PPM      600 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (49)         (50)                                                             
      Cyst                                                          1 (2%)                                                          
      Mineralization                                                1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (49)                                                             
      Hemorrhage                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)                                                             
      Inflammation, Chronic Active                     1 (2%)       4 (8%)                                                          
      Alveolar Epithelium, Hyperplasia                              2 (4%)                                                          
   Nose                                               (50)         (50)                                                             
      Mucosa, Inflammation, Suppurative                1 (2%)                                                                       
      Nasolacrimal Duct, Inflammation, Suppurative     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)                                                             
      Metaplasia, Osseous                              1 (2%)                                                                       
      Nephropathy, Chronic                            14 (28%)     17 (34%)                                                         
   Urinary Bladder                                    (49)         (49)                                                             
      Artery, Inflammation, Chronic Active             1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        O PPM        30 PPM       100 PPM      100 PPM      100 PPM         
                                                   0-0           10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50           50           50           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 6            8            2            7           10            3           
    Natural Death                                      5            5            9            6            7            6           
  Survivors                                                                                                                         
    Terminal Sacrifice                                38           36           38           36           33           39           
    Moribund Sacrifice                                 1                                                                            
    Natural Death                                                   1            1                                      1           
  Missing                                                                                     1                         1           
  Animals Examined Microscopically                    50           50           50           49           50           49           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (46)         (11)         (8)          (11)         (10)         (5)          
      Inflammation, Suppurative                                                  1 (13%)                                            
   Intestine Large, Cecum                             (49)         (13)         (11)         (12)         (16)         (7)          
      Parasite Metazoan                                1 (2%)                                                                       
   Intestine Large, Colon                             (49)         (13)         (12)         (13)         (15)         (7)          
      Parasite Metazoan                                1 (2%)       1 (8%)                                                          
   Intestine Large, Rectum                            (47)         (13)         (11)         (12)         (15)         (8)          
      Parasite Metazoan                                1 (2%)                                              1 (7%)                   
      Prolapse                                                                                                          1 (13%)     
   Intestine Small, Duodenum                          (48)         (12)         (9)          (10)         (15)         (7)          
      Hyperplasia, Atypical                                                                                1 (7%)                   
      Inflammation, Acute, Necrotizing                                                                     1 (7%)                   
      Inflammation, Chronic Active                                                                                      1 (14%)     
   Intestine Small, Jejunum                           (50)         (12)         (17)         (10)         (16)         (8)          
      Inflammation, Acute, Necrotizing                 2 (4%)                    1 (6%)                    1 (6%)                   
      Inflammation, Chronic Active                                               1 (6%)                                             
   Liver                                              (50)         (50)         (50)         (49)         (50)         (49)         
      Angiectasis                                                   1 (2%)                                                          
      Basophilic Focus                                 4 (8%)       3 (6%)       5 (10%)                   1 (2%)       6 (12%)     
      Clear Cell Focus                                 7 (14%)      7 (14%)      2 (4%)       3 (6%)       4 (8%)       5 (10%)     
      Clear Cell Focus, Multiple                                                                                        1 (2%)      
      Cyst                                             1 (2%)                    1 (2%)                    1 (2%)       2 (4%)      
      Degeneration, Cystic                                          3 (6%)       2 (4%)       9 (18%)      7 (14%)      9 (18%)     
      Eosinophilic Focus                               3 (6%)       2 (4%)                    3 (6%)       3 (6%)       5 (10%)     
      Fatty Change                                     5 (10%)      2 (4%)       7 (14%)                   4 (8%)       2 (4%)      
      Fibrosis, Focal                                                                         1 (2%)                                
      Hematopoietic Cell Proliferation                 2 (4%)                    1 (2%)                                             
      Hepatodiaphragmatic Nodule                                                 1 (2%)       1 (2%)                                
      Infarct, Multifocal                              4 (8%)       8 (16%)      5 (10%)     11 (22%)      7 (14%)      6 (12%)     
      Inflammation, Chronic                                                      1 (2%)                                             
      Mineralization                                                             1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        O PPM        30 PPM       100 PPM      100 PPM      100 PPM         
                                                   0-0           10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Mixed Cell Focus                                 3 (6%)       1 (2%)       1 (2%)       2 (4%)                    1 (2%)      
      Necrosis                                         2 (4%)                                                                       
      Necrosis, Multifocal                                                                                              1 (2%)      
      Regeneration, Diffuse                            1 (2%)                                                                       
      Bile Duct, Hyperplasia                           2 (4%)                                              1 (2%)                   
      Centrilobular, Congestion, Chronic                                         1 (2%)                                             
      Centrilobular, Cytomegaly                                    16 (32%)      5 (10%)     33 (67%)     20 (40%)     19 (39%)     
   Mesentery                                          (3)          (2)          (2)                       (3)                       
      Inflammation, Suppurative                        1 (33%)                                             2 (67%)                  
      Artery, Inflammation, Chronic Active             1 (33%)                   1 (50%)                                            
      Fat, Necrosis                                                 1 (50%)                                                         
   Pancreas                                           (50)         (13)         (11)         (13)         (17)         (8)          
      Acinus, Atrophy                                  4 (8%)       1 (8%)       1 (9%)       1 (8%)                                
      Acinus, Focal Cellular Change                    1 (2%)       1 (8%)                                                          
      Artery, Inflammation, Chronic Active                                                    1 (8%)                                
      Duct, Dilatation                                                                        1 (8%)                                
   Stomach, Forestomach                               (50)         (16)         (11)         (18)         (15)         (9)          
      Diverticulum                                                                            1 (6%)                                
      Hyperplasia, Squamous                                                                   4 (22%)                   1 (11%)     
      Epithelium, Hyperplasia                          1 (2%)                    2 (18%)      2 (11%)                               
   Stomach, Glandular                                 (50)         (15)         (9)          (16)         (13)         (9)          
      Inflammation, Acute, Necrotizing                 1 (2%)                                                                       
      Mineralization                                                1 (7%)                                                          
   Tooth                                              (36)         (1)          (5)          (1)          (2)          (2)          
      Incisor, Upper, Dysplasia                       36 (100%)     1 (100%)     5 (100%)     1 (100%)     2 (100%)     2 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (14)         (12)         (13)         (17)         (10)         
      Bacterium                                                                                                         1 (10%)     
      Cardiomyopathy, Chronic Active                                             1 (8%)                                 1 (10%)     
      Atrium, Thrombosis                                                         1 (8%)                                             
      Valve, Inflammation, Suppurative                                                                                  1 (10%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (50)         (14)         (11)         (12)         (17)         (9)          
      Hyperplasia                                      4 (8%)       1 (7%)       1 (9%)                    1 (6%)                   
      Hypertrophy                                     17 (34%)      1 (7%)       2 (18%)      4 (33%)                               
      Necrosis                                                                   1 (9%)                                             
   Adrenal Gland, Medulla                             (50)         (14)         (11)         (11)         (17)         (9)          
      Hyperplasia                                      5 (10%)                                                                      
      Necrosis                                                                   1 (9%)                                             
   Islets, Pancreatic                                 (50)         (13)         (10)         (12)         (17)         (8)          
      Hyperplasia                                      1 (2%)                                 1 (8%)       1 (6%)                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        O PPM        30 PPM       100 PPM      100 PPM      100 PPM         
                                                   0-0           10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
   Pituitary Gland                                    (45)         (11)         (4)          (10)         (14)         (7)          
      Pars Distalis, Hyperplasia                       2 (4%)                                                                       
   Thyroid Gland                                      (49)         (14)         (11)         (13)         (17)         (9)          
      Follicle, Cyst Multilocular                      1 (2%)       1 (7%)                                                          
      Follicular Cell, Hyperplasia                     2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Preputial Gland                                    (5)          (2)          (4)          (2)          (3)          (8)          
      Inflammation, Chronic Active                     1 (20%)      1 (50%)      1 (25%)                   2 (67%)      3 (38%)     
      Duct, Dilatation                                 4 (80%)      1 (50%)      4 (100%)     2 (100%)     1 (33%)      4 (50%)     
   Prostate                                           (50)         (14)         (12)         (13)         (17)         (9)          
      Inflammation, Suppurative                                                                                         2 (22%)     
      Artery, Inflammation, Chronic Active             1 (2%)                                                                       
   Seminal Vesicle                                                 (1)          (1)                       (2)          (1)          
      Inflammation, Chronic Active                                                                                      1 (100%)    
   Testes                                             (50)         (14)         (12)         (13)         (17)         (9)          
      Degeneration                                                                            1 (8%)       1 (6%)                   
      Inflammation, Acute, Necrotizing                                                                                  1 (11%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (50)         (30)         (32)         (27)         (31)         (23)         
      Deep Cervical, Edema                                                                    1 (4%)                                
      Lumbar, Edema                                                                                                     1 (4%)      
      Mandibular, Angiectasis                                                    1 (3%)       1 (4%)       1 (3%)                   
      Mandibular, Edema                                             1 (3%)       1 (3%)                    2 (6%)                   
      Mandibular, Hyperplasia, Lymphoid                                          2 (6%)       1 (4%)       2 (6%)                   
      Renal, Edema                                                                                                      1 (4%)      
   Lymph Node, Mesenteric                             (22)         (22)         (20)         (16)         (20)         (15)         
      Angiectasis                                     15 (68%)     12 (55%)     15 (75%)     11 (69%)      9 (45%)     11 (73%)     
      Edema                                                         2 (9%)                    1 (6%)                                
      Hyperplasia, Lymphoid                            1 (5%)                    1 (5%)       1 (6%)       2 (10%)                  
   Spleen                                             (49)         (21)         (18)         (20)         (25)         (17)         
      Angiectasis, Focal                               1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 4 (8%)       1 (5%)       3 (17%)      3 (15%)      4 (16%)      1 (6%)      
      Hyperplasia, Lymphoid                                                                   1 (5%)                    3 (18%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        O PPM        30 PPM       100 PPM      100 PPM      100 PPM         
                                                   0-0           10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (50)         (15)         (13)         (14)         (20)         (9)          
      Cyst Epithelial Inclusion                                                  1 (8%)                                             
      Inflammation, Acute                                                                                               2 (22%)     
      Inflammation, Chronic Active                     2 (4%)                                                                       
      Subcutaneous Tissue, Fibrosis                                                                        1 (5%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (30)         (40)         (30)         (37)         (35)         
      Femur, Fibrosis, Focal                           1 (2%)                                                                       
      Tarsal, Hyperostosis                            28 (56%)     16 (53%)     31 (78%)     19 (63%)     22 (59%)     27 (77%)     
      Tarsal, Inflammation, Chronic Active                                       1 (3%)                                             
   Skeletal Muscle                                    (1)          (1)          (1)                                                 
      Artery, Inflammation, Chronic Active             1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (14)         (12)         (13)         (18)         (10)         
      Compression                                                                1 (8%)                                             
      Hemorrhage                                                                              1 (8%)       1 (6%)                   
      Hydrocephalus                                                                                        1 (6%)                   
      Necrosis                                                                                             1 (6%)                   
      Artery, Inflammation, Chronic Active             1 (2%)                    1 (8%)                                             
      Meninges, Infiltration Cellular, Lymphocyte      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (19)         (19)         (21)         (20)         (22)         
      Inflammation, Chronic Active                     2 (4%)                    3 (16%)      3 (14%)                               
      Metaplasia, Focal, Squamous                      1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                11 (22%)      1 (5%)                    2 (10%)      1 (5%)       2 (9%)      
      Alveolus, Infiltration Cellular, Histiocyte      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (2)          (3)                       (2)                       (3)          
      Degeneration                                     1 (50%)      1 (33%)                   2 (100%)                  3 (100%)    
      Cornea, Inflammation, Chronic Active             1 (50%)      1 (33%)                                                         
   Harderian Gland                                    (9)          (2)          (2)          (2)          (3)          (4)          
      Hyperplasia                                      3 (33%)                                                                      
      Inflammation, Suppurative                        1 (11%)                                1 (50%)                               
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        O PPM        30 PPM       100 PPM      100 PPM      100 PPM         
                                                   0-0           10-0         1-1          10-3         3-3          0-3            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (16)         (12)         (13)         (18)         (9)          
      Cyst                                             1 (2%)                                                                       
      Hydronephrosis                                   1 (2%)                                                                       
      Infiltration Cellular, Lymphocyte                1 (2%)                                                                       
      Metaplasia, Osseous                              1 (2%)                                                                       
      Nephropathy, Chronic                            36 (72%)      4 (25%)      6 (50%)      4 (31%)      9 (50%)      1 (11%)     
      Artery, Inflammation, Chronic Active             1 (2%)                    1 (8%)                                             
      Pelvis, Inflammation, Suppurative                1 (2%)                                                           2 (22%)     
      Renal Tubule, Hyperplasia                                                                                         1 (11%)     
   Urinary Bladder                                    (49)         (13)         (12)         (13)         (18)         (8)          
      Inflammation, Chronic Active                     1 (2%)                                              2 (11%)      2 (25%)     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          300 PPM      300 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 4            9                                                               
    Natural Death                                      2            7                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                44           34                                                               
  Animals Examined Microscopically                    50           50                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (48)         (50)                                                             
      Inflammation, Acute, Necrotizing                              1 (2%)                                                          
   Intestine Large, Rectum                            (49)         (48)                                                             
      Parasite Metazoan                                2 (4%)       1 (2%)                                                          
   Intestine Small, Ileum                             (49)         (46)                                                             
      Inflammation, Acute, Necrotizing                 1 (2%)       1 (2%)                                                          
   Intestine Small, Jejunum                           (48)         (48)                                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Parasite Metazoan                                1 (2%)                                                                       
   Liver                                              (50)         (49)                                                             
      Basophilic Focus                                 1 (2%)       3 (6%)                                                          
      Clear Cell Focus                                26 (52%)     20 (41%)                                                         
      Degeneration, Cystic                            39 (78%)     29 (59%)                                                         
      Eosinophilic Focus                               5 (10%)      2 (4%)                                                          
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Infarct, Multifocal                              3 (6%)       2 (4%)                                                          
      Inflammation, Chronic                            1 (2%)       1 (2%)                                                          
      Mixed Cell Focus                                 3 (6%)                                                                       
      Centrilobular, Cytomegaly                       46 (92%)     37 (76%)                                                         
   Mesentery                                          (3)          (4)                                                              
      Artery, Inflammation, Chronic Active             1 (33%)                                                                      
   Pancreas                                           (49)         (49)                                                             
      Acinus, Atrophy                                  6 (12%)                                                                      
      Acinus, Depletion Secretory                      1 (2%)                                                                       
      Acinus, Focal Cellular Change                                 2 (4%)                                                          
   Salivary Glands                                    (50)         (49)                                                             
      Inflammation, Granulomatous                                   1 (2%)                                                          
      Necrosis                                                      1 (2%)                                                          
      Acinus, Atrophy                                               1 (2%)                                                          
   Stomach, Forestomach                               (49)         (48)                                                             
      Ulcer                                            1 (2%)                                                                       
      Epithelium, Hyperplasia                          1 (2%)       2 (4%)                                                          
   Stomach, Glandular                                 (49)         (47)                                                             
      Inflammation, Acute, Necrotizing                              4 (9%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          300 PPM      300 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Tooth                                              (44)         (39)                                                             
      Incisor, Upper, Dysplasia                       44 (100%)    38 (97%)                                                         
      Peridontal Tissue, Inflammation, Suppurative     1 (2%)       1 (3%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (49)                                                             
      Artery, Inflammation, Chronic Active             2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (49)         (49)                                                             
      Hyperplasia                                      2 (4%)       4 (8%)                                                          
      Hypertrophy                                     15 (31%)      7 (14%)                                                         
   Islets, Pancreatic                                 (49)         (49)                                                             
      Hyperplasia                                      1 (2%)                                                                       
   Thyroid Gland                                      (50)         (49)                                                             
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Follicle, Cyst Multilocular                                   1 (2%)                                                          
      Follicular Cell, Hyperplasia                     4 (8%)       6 (12%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (49)         (50)                                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Preputial Gland                                    (4)          (8)                                                              
      Inflammation, Chronic Active                                  3 (38%)                                                         
      Duct, Dilatation                                 4 (100%)     7 (88%)                                                         
   Prostate                                           (50)         (50)                                                             
      Inflammation, Suppurative                                     3 (6%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)                                                             
      Femoral, Thrombosis                              1 (2%)                                                                       
   Lymph Node                                         (50)         (47)                                                             
      Mandibular, Angiectasis                          1 (2%)                                                                       
      Mandibular, Edema                                1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   16                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          300 PPM      300 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Mediastinal, Angiectasis                                      1 (2%)                                                          
   Lymph Node, Mesenteric                             (18)         (24)                                                             
      Angiectasis                                     13 (72%)     13 (54%)                                                         
   Spleen                                             (49)         (47)                                                             
      Cyst                                                          1 (2%)                                                          
      Depletion Lymphoid                               1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 2 (4%)       2 (4%)                                                          
   Thymus                                             (43)         (41)                                                             
      Atrophy                                                       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (50)         (50)                                                             
      Inflammation, Acute                              1 (2%)                                                                       
      Inflammation, Chronic Active                                  2 (4%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)                                                             
      Femur, Hyperostosis                                           1 (2%)                                                          
      Tarsal, Hyperostosis                             9 (18%)     13 (26%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (49)                                                             
      Inflammation, Acute                              2 (4%)                                                                       
      Inflammation, Chronic Active                     1 (2%)       2 (4%)                                                          
      Alveolar Epithelium, Hyperplasia                 1 (2%)       6 (12%)                                                         
      Artery, Mediastinum, Inflammation, Chronic                                                                                    
          Active                                       1 (2%)                                                                       
   Nose                                               (50)         (50)                                                             
      Mucosa, Inflammation, Suppurative                             1 (2%)                                                          
      Nasolacrimal Duct, Inflammation, Suppurative     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   17                                                              
NTP Experiment-Test: 05075-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         DIPHENYLHYDANTOIN                                     Date: 09/09/94  
Route: DOSED FEED                                                                                                 Time: 15:41:56  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          300 PPM      300 PPM                                                             
                                                    10-10        0-10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (2)          (1)                                                              
      Degeneration                                     2 (100%)     1 (100%)                                                        
   Harderian Gland                                    (4)          (5)                                                              
      Hyperplasia                                      1 (25%)      1 (20%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)                                                             
      Embolus Bacterial                                             1 (2%)                                                          
      Nephropathy, Chronic                            39 (78%)     35 (70%)                                                         
      Artery, Inflammation, Chronic Active             1 (2%)                                                                       
      Pelvis, Inflammation, Suppurative                             2 (4%)                                                          
   Urinary Bladder                                    (50)         (50)                                                             
      Concretion                                                    1 (2%)                                                          
      Inflammation, Chronic Active                                  5 (10%)                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
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