https://ntp.niehs.nih.gov/go/18909

TDMS Study 92013-06 Pathology Tables

NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04
Route: DOSED FEED                                                                                                 Time: 14:34:49
                                                         FINAL #1 MICE
       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
                                                              Page   1
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 3            4            3            3                                     
    Natural Death                                      4            6            4            7                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                42           40           41           39                                     
    Natural Death                                      1                         2            1                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Intestine Large, Colon                             (48)         (50)         (50)         (49)                                   
      Squamous Cell Carcinoma, Metastatic, Stomach,                                                                                 
           Forestomach                                                           1 (2%)                                             
   Intestine Large, Cecum                             (49)         (48)         (46)         (46)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
   Intestine Small, Duodenum                          (48)         (47)         (49)         (48)                                   
      Carcinoma                                                                  2 (4%)                                             
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Polyp Adenomatous                                1 (2%)                                                                       
   Intestine Small, Jejunum                           (50)         (48)         (47)         (47)                                   
   Intestine Small, Ileum                             (48)         (45)         (48)         (48)                                   
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma                         1 (2%)       2 (4%)                    1 (2%)                                
      Hepatocellular Adenoma                           4 (8%)       5 (10%)                   1 (2%)                                
      Histiocytic Sarcoma                                           1 (2%)       1 (2%)       2 (4%)                                
      Mast Cell Tumor Malignant                                                               1 (2%)                                
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
      Squamous Cell Carcinoma, Metastatic, Stomach,                                                                                 
           Forestomach                                                           1 (2%)                                             
   Mesentery                                          (3)          (7)          (7)          (4)                                    
      Carcinoma, Metastatic, Mammary Gland                          1 (14%)                                                         
      Histiocytic Sarcoma                                           1 (14%)                                                         
      Squamous Cell Carcinoma, Metastatic, Stomach,                                                                                 
           Forestomach                                                           1 (14%)                                            
   Pancreas                                           (49)         (48)         (48)         (49)                                   
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
   Salivary Glands                                    (50)         (48)         (50)         (49)                                   
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
                                                             Page   2                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM - cont                                                                                                            
      Squamous Cell Carcinoma                                                    2 (4%)                                             
      Squamous Cell Papilloma                          2 (4%)                    1 (2%)       2 (4%)                                
   Stomach, Glandular                                 (49)         (49)         (50)         (49)                                   
      Adenoma                                                                                 1 (2%)                                
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
      Squamous Cell Carcinoma, Metastatic, Stomach,                                                                                 
           Forestomach                                                           1 (2%)                                             
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
      Capsule, Adenoma                                              1 (2%)                                                          
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Pheochromocytoma Malignant                       1 (2%)                                 1 (2%)                                
      Pheochromocytoma Benign                                       1 (2%)                                                          
   Islets, Pancreatic                                 (49)         (48)         (47)         (49)                                   
      Adenoma                                                       3 (6%)                                                          
      Carcinoma                                                     1 (2%)       1 (2%)                                             
   Pituitary Gland                                    (49)         (46)         (49)         (50)                                   
      Pars Distalis, Adenoma                           5 (10%)      4 (9%)       3 (6%)       2 (4%)                                
   Thyroid Gland                                      (50)         (49)         (50)         (48)                                   
      Bilateral, Adenoma                               1 (2%)                                                                       
      Follicular Cell, Adenoma                                                   1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                             Page   3                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Ovary                                              (48)         (49)         (49)         (50)                                   
      Cystadenoma                                      2 (4%)                    1 (2%)       1 (2%)                                
      Granulosa Cell Tumor Benign                      2 (4%)                                                                       
      Hemangiosarcoma                                               1 (2%)                                                          
      Histiocytic Sarcoma                                                        1 (2%)                                             
      Luteoma                                                       1 (2%)       2 (4%)       2 (4%)                                
      Tubulostromal Adenoma                                         1 (2%)                    1 (2%)                                
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Carcinoma                                                     1 (2%)                                                          
      Hemangiosarcoma                                               1 (2%)                    1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)       1 (2%)       2 (4%)       2 (4%)                                
      Leiomyoma                                                                  1 (2%)                                             
      Polyp Stromal                                                 2 (4%)                    2 (4%)                                
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
      Sarcoma Stromal                                                            1 (2%)                                             
      Schwannoma Malignant                             1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                               1 (2%)                    1 (2%)                                
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Mast Cell Tumor Malignant                                                               1 (2%)                                
   Lymph Node                                         (3)          (9)          (12)         (7)                                    
      Iliac, Histiocytic Sarcoma                                    1 (11%)                                                         
      Mediastinal, Histiocytic Sarcoma                                                        1 (14%)                               
      Pancreatic, Squamous Cell Carcinoma,                                                                                          
          Metastatic, Stomach, Forestomach                                       1 (8%)                                             
   Lymph Node, Mandibular                             (47)         (47)         (48)         (48)                                   
      Histiocytic Sarcoma                                           1 (2%)                                                          
   Lymph Node, Mesenteric                             (49)         (47)         (49)         (50)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Mast Cell Tumor Malignant                                                               1 (2%)                                
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
   Spleen                                             (49)         (49)         (49)         (49)                                   
      Fibrosarcoma, Metastatic, Skin                   1 (2%)                                                                       
      Hemangiosarcoma                                  2 (4%)       2 (4%)                                                          
      Histiocytic Sarcoma                                                        1 (2%)                                             
      Mast Cell Tumor Malignant                                                               1 (2%)                                
   Thymus                                             (49)         (49)         (50)         (48)                                   
____________________________________________________________________________________________________________________________________
                                                             Page   4                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Mammary Gland                                      (50)         (50)         (49)         (49)                                   
      Adenoma                                                                                 1 (2%)                                
      Carcinoma                                        1 (2%)       1 (2%)                    1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Basal Cell Carcinoma                                                       1 (2%)                                             
      Subcutaneous Tissue, Fibrosarcoma                1 (2%)                                 1 (2%)                                
      Subcutaneous Tissue, Hemangiosarcoma             2 (4%)                                 1 (2%)                                
      Subcutaneous Tissue, Melanoma Benign                          1 (2%)                                                          
      Subcutaneous Tissue, Sarcoma, Poorly                                                                                          
          Differentiated                               1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Bone                                               (50)         (50)         (50)         (50)                                   
      Osteosarcoma                                                                            1 (2%)                                
   Skeletal Muscle                                    (1)          (1)          (2)          (2)                                    
      Sarcoma, Metastatic, Skin                        1 (100%)                                                                     
      Squamous Cell Carcinoma, Metastatic, Stomach,                                                                                 
           Forestomach                                                           2 (100%)                                           
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   Brain                                              (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
      Histiocytic Sarcoma                                           1 (2%)                                                          
      Mast Cell Tumor Malignant                                                               1 (2%)                                
   Spinal Cord                                                     (2)                       (1)                                    
      Osteosarcoma, Metastatic, Bone                                                          1 (100%)                              
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                  8 (16%)     12 (24%)      6 (12%)                               
      Alveolar/Bronchiolar Adenoma, Multiple                                     4 (8%)       2 (4%)                                
      Alveolar/Bronchiolar Carcinoma                   3 (6%)                    2 (4%)       6 (12%)                               
      Alveolar/Bronchiolar Carcinoma, Multiple                                                1 (2%)                                
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
      Histiocytic Sarcoma                                                                     2 (4%)                                
                                                             Page   5                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
RESPIRATORY SYSTEM - cont                                                                                                           
      Mast Cell Tumor Malignant                                                               1 (2%)                                
      Osteosarcoma, Metastatic, Bone                                                          1 (2%)                                
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
   Nose                                               (50)         (49)         (50)         (50)                                   
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Adenoma                                          6 (12%)      1 (2%)       5 (10%)      6 (12%)                               
      Carcinoma                                        1 (2%)       1 (2%)                    2 (4%)                                
   Zymbal's Gland                                     (1)                       (1)                                                 
      Carcinoma                                        1 (100%)                  1 (100%)                                           
____________________________________________________________________________________________________________________________________
 URINARY SYSTEM                                                                                                                     
   Kidney                                             (49)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
      Histiocytic Sarcoma                                                        1 (2%)                                             
   Urinary Bladder                                    (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                                           1 (2%)                                                          
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)       1 (2%)       3 (6%)       2 (4%)                                
      Lymphoma Malignant                               7 (14%)     10 (20%)     12 (24%)     13 (26%)                               
____________________________________________________________________________________________________________________________________
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   6                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            29          36          37          40                                       
     Total Primary Neoplasms                           46          50          55          66                                       
   Total Animals with Benign Neoplasms                 18          23          23          21                                       
     Total Benign Neoplasms                            23          28          30          28                                       
   Total Animals with Malignant Neoplasms              20          20          23          29                                       
     Total Malignant Neoplasms                         23          22          25          38                                       
   Total Animals with Metastatic Neoplasms              2           1           2           1                                       
     Total Metastatic Neoplasm                          9           6           7           2                                       
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
____________________________________________________________________________________________________________________________________
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: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                      4            6            8                                                  
    Moribund Sacrifice                                 1                                      3                                     
  Survivors                                                                                                                         
    Natural Death                                      1                                                                            
    Terminal Sacrifice                                44           44           42           46                                     
  Other                                                                                       1                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Intestine Small, Duodenum                          (50)         (49)         (48)         (50)                                   
      Carcinoma                                                     2 (4%)                                                          
      Polyp Adenomatous                                             1 (2%)                                                          
   Intestine Small, Jejunum                           (48)         (47)         (48)         (50)                                   
      Carcinoma                                                     1 (2%)                                                          
   Intestine Small, Ileum                             (49)         (46)         (48)         (49)                                   
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                                            1 (2%)       1 (2%)                                
      Hemangiosarcoma, Multiple                                                  1 (2%)                                             
      Hepatocellular Carcinoma                         8 (16%)     11 (22%)     10 (20%)      7 (14%)                               
      Hepatocellular Carcinoma, Multiple               2 (4%)       2 (4%)       1 (2%)       3 (6%)                                
      Hepatocellular Adenoma                          14 (28%)      7 (14%)     10 (20%)     11 (22%)                               
      Hepatocellular Adenoma, Multiple                 3 (6%)       2 (4%)       1 (2%)                                             
   Mesentery                                          (4)          (7)          (2)          (3)                                    
      Hemangiosarcoma                                               1 (14%)                   1 (33%)                               
      Hepatocellular Carcinoma, Metastatic, Liver                   1 (14%)                                                         
      Sarcoma, Poorly Differentiated                                1 (14%)                                                         
   Oral Mucosa                                                                  (1)                                                 
      Squamous Cell Carcinoma                                                    1 (100%)                                           
   Pancreas                                           (49)         (49)         (50)         (50)                                   
      Sarcoma, Metastatic, Mesentery                                1 (2%)                                                          
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (49)         (50)         (50)         (50)                                   
      Squamous Cell Carcinoma                          1 (2%)                                                                       
      Squamous Cell Papilloma                                       2 (4%)                    3 (6%)                                
   Stomach, Glandular                                 (49)         (50)         (49)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver                                1 (2%)                                             
                                                             Page   8                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                                            1 (2%)                                             
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)                                                                       
      Capsule, Adenoma                                 3 (6%)       1 (2%)       1 (2%)                                             
      Capsule, Carcinoma                                            1 (2%)                                                          
   Islets, Pancreatic                                 (49)         (49)         (50)         (50)                                   
      Adenoma                                                       1 (2%)                    1 (2%)                                
   Pituitary Gland                                    (49)         (48)         (49)         (50)                                   
      Pars Distalis, Adenoma                                        1 (2%)                                                          
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Follicular Cell, Adenoma                         1 (2%)       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   Tissue NOS                                         (1)                                                                           
      Schwannoma Malignant                             1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Prostate                                           (50)         (50)         (50)         (50)                                   
      Carcinoma                                                                  1 (2%)                                             
   Testes                                             (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                                            1 (2%)       1 (2%)                                
      Interstitial Cell, Adenoma                                    2 (4%)                                                          
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       1 (2%)                                                          
   Lymph Node                                         (2)          (2)          (1)          (2)                                    
   Lymph Node, Mandibular                             (48)         (50)         (48)         (45)                                   
   Lymph Node, Mesenteric                             (49)         (48)         (48)         (50)                                   
                                                             Page   9                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - cont                                                                                                         
   Spleen                                             (49)         (49)         (50)         (50)                                   
      Hemangiosarcoma                                               1 (2%)                    1 (2%)                                
   Thymus                                             (48)         (49)         (45)         (45)                                   
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Skin                                               (50)         (50)         (50)         (49)                                   
      Squamous Cell Carcinoma                                       1 (2%)                                                          
      Sebaceous Gland, Adenoma                                                                1 (2%)                                
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Skeletal Muscle                                    (1)          (2)          (1)          (1)                                    
      Carcinoma, Metastatic, Prostate                                            1 (100%)                                           
      Hemangiosarcoma                                  1 (100%)                                                                     
      Sarcoma, Metastatic, Mesentery                                1 (50%)                                                         
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     6 (12%)     10 (20%)     10 (20%)     14 (28%)                               
      Alveolar/Bronchiolar Adenoma, Multiple           2 (4%)       1 (2%)       3 (6%)       1 (2%)                                
      Alveolar/Bronchiolar Carcinoma                   2 (4%)       3 (6%)       4 (8%)       7 (14%)                               
      Alveolar/Bronchiolar Carcinoma, Multiple                      1 (2%)                    1 (2%)                                
      Carcinoma, Metastatic, Prostate                                            1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic, Liver      3 (6%)       3 (6%)       3 (6%)       3 (6%)                                
      Schwannoma Malignant, Metastatic, Tissue NOS     1 (2%)                                                                       
      Mediastinum, Hemangiosarcoma                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                             Page  10                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Adenoma                                          3 (6%)       8 (16%)      4 (8%)       6 (12%)                               
      Adenoma, Multiple                                1 (2%)                                 1 (2%)                                
      Carcinoma                                        1 (2%)                                 1 (2%)                                
      Bilateral, Adenoma                                            1 (2%)                                                          
      Bilateral, Carcinoma                                          1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 URINARY SYSTEM                                                                                                                     
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
      Renal Tubule, Adenoma                                                      2 (4%)                                             
      Renal Tubule, Carcinoma                                                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Lymphoma Malignant                               3 (6%)       3 (6%)       4 (8%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  11                                                               
NTP Experiment-Test: 92013-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                         4-METHYLIMIDAZOLE                                     Date: 01/12/04  
Route: DOSED FEED                                                                                                 Time: 14:34:49  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0 PPM        312 PPM      625 PPM      1250 PPM                                  
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            34          38          36          39                                       
     Total Primary Neoplasms                           55          68          57          63                                       
   Total Animals with Benign Neoplasms                 26          29          23          27                                       
     Total Benign Neoplasms                            34          38          31          38                                       
   Total Animals with Malignant Neoplasms              15          25          21          22                                       
     Total Malignant Neoplasms                         21          30          26          25                                       
   Total Animals with Metastatic Neoplasms              4           3           4           3                                       
     Total Metastatic Neoplasm                          5           6           6           3                                       
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
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