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TDMS Study 92013-05 Pathology Tables

NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04
Route: DOSED FEED                                                                                                 Time: 08:36:54

                                                         FINAL #1 RATS




       Facility:  Southern Research Institute

       Chemical CAS #:  822-36-6

       Lock Date:  09/13/02

       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

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NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        1250 PPM     2500 PPM     5000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                      2            6           11            6                                     
    Moribund Sacrifice                                 5            5            5            9                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                40           39           34           33                                     
    Natural Death                                      3                                      2                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)         (48)         (45)         (46)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Intestine Large, Cecum                             (48)         (46)         (43)         (43)                                   
   Intestine Small, Duodenum                          (49)         (48)         (43)         (45)                                   
   Intestine Small, Ileum                             (45)         (47)         (42)         (43)                                   
   Liver                                              (50)         (50)         (48)         (50)                                   
      Cholangiocarcinoma                                                         1 (2%)                                             
      Hepatocellular Adenoma                                                     1 (2%)       2 (4%)                                
      Histiocytic Sarcoma                              2 (4%)                                                                       
      Osteosarcoma, Metastatic, Uncertain Primary                                                                                   
          Site                                                                   1 (2%)                                             
   Mesentery                                          (9)          (7)          (11)         (8)                                    
      Fibrosarcoma                                     1 (11%)                                                                      
      Histiocytic Sarcoma                              1 (11%)                                                                      
   Pancreas                                           (49)         (49)         (47)         (47)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (50)         (50)         (49)         (50)                                   
   Stomach, Glandular                                 (50)         (50)         (49)         (49)                                   
   Tongue                                                          (5)          (4)          (3)                                    
      Squamous Cell Papilloma                                       1 (20%)      1 (25%)      1 (33%)                               
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                                                             Page   2                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        1250 PPM     2500 PPM     5000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (48)         (50)                                   
      Schwannoma Benign                                1 (2%)       1 (2%)       3 (6%)                                             
      Schwannoma Benign, Multiple                                                1 (2%)                                             
      Schwannoma Malignant                                                       1 (2%)                                             
      Epicardium, Alveolar/Bronchiolar Carcinoma,                                                                                   
           Metastatic, Lung                                         1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)                    1 (2%)       1 (2%)                                
      Carcinoma                                                                  1 (2%)                                             
   Adrenal Medulla                                    (48)         (50)         (50)         (50)                                   
      Pheochromocytoma Malignant                       1 (2%)                                                                       
      Pheochromocytoma Benign                          1 (2%)       1 (2%)       2 (4%)       2 (4%)                                
      Bilateral, Pheochromocytoma Benign               1 (2%)                                                                       
   Islets, Pancreatic                                 (49)         (50)         (48)         (47)                                   
      Adenoma                                                       1 (2%)                                                          
      Mixed Tumor Benign                                            1 (2%)                                                          
   Pituitary Gland                                    (48)         (50)         (50)         (50)                                   
      Pars Distalis, Adenoma                          29 (60%)     19 (38%)     20 (40%)      9 (18%)                               
      Pars Distalis, Carcinoma                                      1 (2%)                                                          
   Thyroid Gland                                      (47)         (44)         (40)         (45)                                   
      Bilateral, C-Cell, Adenoma                                                 1 (3%)                                             
      C-Cell, Adenoma                                 10 (21%)      8 (18%)      5 (13%)      8 (18%)                               
      C-Cell, Carcinoma                                1 (2%)                    2 (5%)                                             
      Follicular Cell, Adenoma                         2 (4%)       3 (7%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (5)          (3)          (6)          (6)                                    
      Neoplasm NOS                                                               1 (17%)                                            
      Mediastinum, Alveolar/Bronchiolar Carcinoma,                                                                                  
           Metastatic, Lung                                         1 (33%)                                                         
      Mediastinum, Schwannoma Malignant                1 (20%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   3                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        1250 PPM     2500 PPM     5000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (50)         (50)         (50)                                   
      Adenoma                                          8 (16%)      1 (2%)                                                          
      Carcinoma                                        2 (4%)       1 (2%)                                                          
   Ovary                                              (50)         (50)         (48)         (50)                                   
      Granulosa-Theca Tumor Malignant                               1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Oviduct                                                                      (2)          (1)                                    
   Uterus                                             (50)         (50)         (48)         (50)                                   
      Carcinoma                                                                  1 (2%)                                             
      Endometrium, Polyp Stromal                      16 (32%)      5 (10%)      2 (4%)       2 (4%)                                
      Endometrium, Sarcoma Stromal                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (48)         (49)         (48)                                   
      Osteosarcoma, Metastatic, Bone                   1 (2%)                                                                       
   Lymph Node                                         (24)         (11)         (24)         (35)                                   
      Mediastinal, Carcinoma, Metastatic, Thyroid                                                                                   
          Gland                                        1 (4%)                                                                       
      Pancreatic, Histiocytic Sarcoma                  2 (8%)                                                                       
   Lymph Node, Mandibular                             (1)          (3)          (1)          (4)                                    
   Lymph Node, Mesenteric                             (49)         (49)         (49)         (47)                                   
   Spleen                                             (50)         (48)         (47)         (48)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Thymus                                             (47)         (50)         (48)         (48)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                     1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (49)         (50)         (50)                                   
      Carcinoma                                        2 (4%)       1 (2%)       2 (4%)                                             
      Fibroadenoma                                    20 (40%)      5 (10%)      3 (6%)       1 (2%)                                
      Fibroadenoma, Multiple                           4 (8%)       1 (2%)       1 (2%)                                             
   Skin                                               (50)         (50)         (50)         (50)                                   
      Basal Cell Adenoma                                                                      1 (2%)                                
      Squamous Cell Papilloma                          1 (2%)                                                                       
      Trichoepithelioma                                1 (2%)                                                                       
      Pinna, Neural Crest Tumor                                                               1 (2%)                                
      Subcutaneous Tissue, Fibroma                     1 (2%)       1 (2%)       5 (10%)                                            
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   4                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        1250 PPM     2500 PPM     5000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - cont                                                                                                         
      Subcutaneous Tissue, Histiocytic Sarcoma         1 (2%)                                                                       
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 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Osteosarcoma                                     1 (2%)       1 (2%)                                                          
      Maxilla, Sarcoma                                                                        1 (2%)                                
   Skeletal Muscle                                                 (1)          (1)                                                 
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                     1 (100%)                                                        
      Carcinoma, Metastatic, Thyroid Gland                                       1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                         1 (2%)                                                          
      Carcinoma, Metastatic, Pituitary Gland                        1 (2%)                                                          
   Spinal Cord                                        (7)          (3)          (24)         (50)                                   
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 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                                                       (1)                                                 
      Carcinoma, Metastatic, Thyroid Gland                                       1 (100%)                                           
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Carcinoma                                2 (4%)                                                          
      Histiocytic Sarcoma, Metastatic, Uncertain                                                                                    
          Primary Site                                 1 (2%)                                                                       
      Osteosarcoma, Metastatic, Bone                                1 (2%)                                                          
   Nose                                               (49)         (50)         (50)         (50)                                   
   Trachea                                            (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Thyroid Gland                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (48)         (45)         (40)         (45)                                   
      Lids, Neural Crest Tumor                                      1 (2%)       1 (3%)                                             
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
   Zymbal's Gland                                                  (3)          (1)                                                 
      Carcinoma                                                     1 (33%)      1 (100%)                                           
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   5                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        1250 PPM     2500 PPM     5000 PPM                                  
                                                                                                                                    
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SPECIAL SENSES SYSTEM - cont                                                                                                        
      Carcinosarcoma                                                1 (33%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (48)         (48)         (43)         (43)                                   
      Bilateral, Renal Tubule, Adenoma                              1 (2%)                                                          
      Pelvis, Transitional Epithelium, Papilloma       1 (2%)                                                                       
   Urinary Bladder                                    (49)         (50)         (49)         (48)                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
                                                                                                                                    
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              2 (4%)                                                                       
      Leukemia Mononuclear                             9 (18%)      7 (14%)     16 (32%)     20 (40%)                               
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     *   Number of animals with any tissue examined microscopically                                                                 
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   6                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        1250 PPM     2500 PPM     5000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            48          39          42          36                                       
     Total Primary Neoplasms                          118          67          73          49                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 48          32          29          20                                       
     Total Benign Neoplasms                            97          49          46          27                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              19          15          24          21                                       
     Total Malignant Neoplasms                         21          17          25          21                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              3           3           2                                                   
     Total Metastatic Neoplasm                          3           6           4                                                   
                                                                                                                                    
   Total Animals with Malignant Neoplasms               1                       1                                                   
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                              1           2           1                                       
     Total Uncertain Neoplasms                                      1           2           1                                       
                                                                                                                                    
                                                                                                                                    
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a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   7                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2500 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                13           11           12           10                                     
    Natural Death                                      6            5            5            8                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                31           34           33           32                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (48)         (49)         (49)         (46)                                   
   Intestine Large, Cecum                             (46)         (46)         (46)         (46)                                   
   Intestine Small, Duodenum                          (49)         (48)         (47)         (47)                                   
   Intestine Small, Jejunum                           (47)         (45)         (45)         (43)                                   
   Intestine Small, Ileum                             (46)         (45)         (45)         (44)                                   
   Liver                                              (50)         (50)         (50)         (50)                                   
      Basal Cell Carcinoma, Metastatic, Skin                                     1 (2%)                                             
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Ito Cell Tumor Benign                                                      1 (2%)                                             
   Mesentery                                          (13)         (10)         (11)         (10)                                   
      Basal Cell Carcinoma, Metastatic, Skin                                     1 (9%)                                             
      Histiocytic Sarcoma                                                                     1 (10%)                               
   Pancreas                                           (50)         (48)         (48)         (49)                                   
      Acinus, Adenoma                                  1 (2%)                                 2 (4%)                                
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
      Fibrosarcoma                                                               1 (2%)                                             
   Stomach, Forestomach                               (50)         (50)         (50)         (49)                                   
   Stomach, Glandular                                 (50)         (50)         (49)         (49)                                   
   Tongue                                                          (3)          (1)          (1)                                    
      Squamous Cell Carcinoma                                       1 (33%)                                                         
      Squamous Cell Papilloma                                       1 (33%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
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                                                             Page   8                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2500 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)                                                                       
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Pheochromocytoma Malignant                                    2 (4%)                                                          
      Pheochromocytoma Complex                         2 (4%)                                                                       
      Pheochromocytoma Benign                          6 (12%)      3 (6%)       3 (6%)       3 (6%)                                
      Bilateral, Pheochromocytoma Benign               2 (4%)       2 (4%)                                                          
   Islets, Pancreatic                                 (50)         (49)         (49)         (49)                                   
      Adenoma                                          3 (6%)       2 (4%)       1 (2%)       1 (2%)                                
      Carcinoma                                                                  1 (2%)                                             
   Parathyroid Gland                                  (48)         (50)         (48)         (50)                                   
      Adenoma                                          1 (2%)                                                                       
   Pituitary Gland                                    (49)         (49)         (48)         (48)                                   
      Pars Distalis, Adenoma                          16 (33%)     13 (27%)     10 (21%)      7 (15%)                               
      Pars Intermedia, Adenoma                                                                1 (2%)                                
   Thyroid Gland                                      (47)         (46)         (48)         (44)                                   
      Chemodectoma Benign                                                                     1 (2%)                                
      Bilateral, C-Cell, Adenoma                                    1 (2%)                    1 (2%)                                
      C-Cell, Adenoma                                 11 (23%)      6 (13%)      3 (6%)       9 (20%)                               
      C-Cell, Carcinoma                                                          2 (4%)                                             
      Follicular Cell, Adenoma                                      1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                                      (2)          (3)          (1)                                    
   Tissue NOS                                         (6)          (4)          (6)          (5)                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
   Preputial Gland                                    (50)         (50)         (50)         (49)                                   
      Adenoma                                          2 (4%)       1 (2%)                                                          
      Carcinoma                                                                  1 (2%)                                             
   Prostate                                           (50)         (50)         (50)         (49)                                   
   Seminal Vesicle                                    (50)         (50)         (50)         (50)                                   
   Testes                                             (50)         (50)         (50)         (50)                                   
      Bilateral, Interstitial Cell, Adenoma           40 (80%)     40 (80%)     34 (68%)     31 (62%)                               
      Interstitial Cell, Adenoma                       6 (12%)      4 (8%)      13 (26%)     14 (28%)                               
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                                                             Page   9                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2500 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (47)         (50)         (48)         (50)                                   
   Lymph Node                                         (19)         (18)         (26)         (27)                                   
   Lymph Node, Mandibular                                          (1)          (1)          (2)                                    
   Lymph Node, Mesenteric                             (50)         (48)         (48)         (49)                                   
   Spleen                                             (50)         (48)         (48)         (49)                                   
      Fibroma                                                       1 (2%)                                                          
   Thymus                                             (48)         (49)         (46)         (45)                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (47)         (46)         (41)         (45)                                   
      Fibroadenoma                                     3 (6%)       1 (2%)       1 (2%)       1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Basal Cell Adenoma                               1 (2%)                    1 (2%)       2 (4%)                                
      Basal Cell Carcinoma                                                       1 (2%)                                             
      Keratoacanthoma                                  1 (2%)                    3 (6%)                                             
      Squamous Cell Carcinoma                          1 (2%)                                                                       
      Subcutaneous Tissue, Fibroma                     7 (14%)      2 (4%)       4 (8%)       3 (6%)                                
      Subcutaneous Tissue, Fibroma, Multiple           1 (2%)                                                                       
      Subcutaneous Tissue, Hemangioma                                            1 (2%)                                             
      Subcutaneous Tissue, Histiocytic Sarcoma                                   1 (2%)                                             
      Subcutaneous Tissue, Lipoma                                                             1 (2%)                                
      Subcutaneous Tissue, Sarcoma                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                                 (2)          (2)                                                 
      Histiocytic Sarcoma                                                        1 (50%)                                            
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 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                                                   1 (2%)                                
      Glioma Malignant                                                           1 (2%)       1 (2%)                                
      Pineal Gland, Neoplasm NOS                                    1 (2%)                                                          
   Spinal Cord                                        (2)          (3)          (2)          (3)                                    
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                                                             Page  10                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2500 PPM                                  
                                                                                                                                    
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 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                  1 (2%)                    1 (2%)                                
      Alveolar/Bronchiolar Carcinoma                                             1 (2%)                                             
      Basal Cell Carcinoma, Metastatic, Skin                                     1 (2%)                                             
      Chordoma, Metastatic, Uncertain Primary Site                                            1 (2%)                                
   Nose                                               (49)         (50)         (50)         (50)                                   
      Olfactory Epithelium, Carcinoma                                            1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
   Zymbal's Gland                                     (3)          (1)          (2)                                                 
      Carcinoma                                        3 (100%)     1 (100%)     2 (100%)                                           
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 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (48)         (49)         (48)         (50)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Sarcoma                                          1 (2%)                                                                       
   Urinary Bladder                                    (49)         (50)         (50)         (50)                                   
      Transitional Epithelium, Papilloma                                         1 (2%)                                             
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
                                                                                                                                    
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                                                        1 (2%)       1 (2%)                                
      Leukemia Mononuclear                            15 (30%)     18 (36%)     22 (44%)     20 (40%)                               
      Lymphoma Malignant                                                                      1 (2%)                                
      Mesothelioma Malignant                                        2 (4%)       3 (6%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  11                                                               
                                                                                                                                   
NTP Experiment-Test: 92013-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 12/06/04  
Route: DOSED FEED                                                                                                 Time: 08:36:54  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2500 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            50          49          50          50                                       
     Total Primary Neoplasms                          124         104         114         103                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 50          49          48          47                                       
     Total Benign Neoplasms                           102          79          76          78                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              22          21          30          23                                       
     Total Malignant Neoplasms                         22          24          38          25                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms                                      2           1                                       
     Total Metastatic Neoplasm                                                 19           1                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms                                       1           1                                       
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                              1                                                               
     Total Uncertain Neoplasms                                      1                                                               
                                                                                                                                    
                                                                                                                                    
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a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  12                                                               
                                                                                                                                   
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