https://ntp.niehs.nih.gov/go/6845

TDMS Study 97006-02 Pathology Tables

NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59
                                                          FINAL#1 MICE
       Facility:  Battelle Northwest
       Chemical CAS #:  108-10-1
       Lock Date:  01/24/03
       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: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                10            9            6            9                                     
    Natural Death                                      5            3            5            3                                     
    Accidently Killed                                               1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                35           37           39           38                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Gallbladder                                        (42)         (44)         (34)         (40)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Intestine Large, Colon                             (48)         (48)         (49)         (49)                                   
   Intestine Large, Rectum                            (47)         (48)         (48)         (49)                                   
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
   Intestine Large, Cecum                             (46)         (48)         (47)         (49)                                   
      Adenoma                                                       1 (2%)                                                          
      Histiocytic Sarcoma                                                        1 (2%)                                             
   Intestine Small, Duodenum                          (47)         (48)         (47)         (48)                                   
      Adenoma                                          1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Intestine Small, Jejunum                           (48)         (47)         (47)         (48)                                   
      Carcinoma                                                                  1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Intestine Small, Ileum                             (48)         (47)         (47)         (47)                                   
      Histiocytic Sarcoma                                                        1 (2%)                                             
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       2 (4%)       1 (2%)                                             
      Hepatoblastoma                                   1 (2%)                                                                       
      Hepatocellular Carcinoma                         3 (6%)       4 (8%)       4 (8%)      11 (22%)                               
      Hepatocellular Carcinoma, Multiple               3 (6%)       1 (2%)       2 (4%)                                             
      Hepatocellular Adenoma                          11 (22%)     10 (20%)     12 (24%)      9 (18%)                               
      Hepatocellular Adenoma, Multiple                 2 (4%)       5 (10%)      8 (16%)     14 (28%)                               
      Hepatocholangiocarcinoma                         1 (2%)       1 (2%)                                                          
      Histiocytic Sarcoma                              2 (4%)                    1 (2%)       5 (10%)                               
   Mesentery                                          (11)         (11)         (13)         (8)                                    
      Hemangiosarcoma, Metastatic, Spleen                                        1 (8%)                                             
      Hemangiosarcoma, Metastatic, Uterus                                        1 (8%)                                             
                                                             Page   2                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM - cont                                                                                                            
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (9%)                                                          
      Histiocytic Sarcoma                                                                     1 (13%)                               
      Sarcoma, Metastatic, Skin                        1 (9%)                                                                       
   Pancreas                                           (50)         (50)         (49)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)       1 (2%)                                                          
      Histiocytic Sarcoma                              2 (4%)                    1 (2%)       1 (2%)                                
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
      Carcinoma                                        1 (2%)                                                                       
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Squamous Cell Carcinoma                                                                 1 (2%)                                
      Squamous Cell Papilloma                          1 (2%)                    3 (6%)                                             
   Stomach, Glandular                                 (49)         (50)         (48)         (49)                                   
   Tooth                                              (1)                                    (1)                                    
      Histiocytic Sarcoma                                                                     1 (100%)                              
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Hemangioma                                                                 1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver                                             1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       2 (4%)                                
   Adrenal Medulla                                    (50)         (50)         (49)         (49)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Pheochromocytoma Benign                          2 (4%)                                 1 (2%)                                
   Islets, Pancreatic                                 (50)         (50)         (49)         (50)                                   
      Carcinoma                                                                               1 (2%)                                
   Parathyroid Gland                                  (28)         (33)         (30)         (36)                                   
      Adenoma                                                                    1 (3%)                                             
   Pituitary Gland                                    (50)         (49)         (48)         (49)                                   
      Histiocytic Sarcoma                                                        1 (2%)       1 (2%)                                
                                                             Page   3                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
ENDOCRINE SYSTEM - cont                                                                                                             
      Pars Distalis, Adenoma                           7 (14%)      9 (18%)      4 (8%)       6 (12%)                               
      Pars Intermedia, Adenoma                                                   2 (4%)                                             
   Thyroid Gland                                      (50)         (50)         (49)         (48)                                   
      C-Cell, Adenoma                                                                         1 (2%)                                
      C-Cell, Carcinoma                                1 (2%)                                                                       
      Follicular Cell, Carcinoma                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   Peritoneum                                                      (2)          (1)                                                 
      Hemangiosarcoma, Metastatic, Spleen                           1 (50%)                                                         
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (50%)                                                         
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Clitoral Gland                                     (45)         (42)         (41)         (42)                                   
      Hemangiosarcoma, Metastatic, Spleen                           1 (2%)                                                          
   Ovary                                              (49)         (50)         (48)         (50)                                   
      Cystadenoma                                                   2 (4%)       1 (2%)       3 (6%)                                
      Histiocytic Sarcoma                              2 (4%)                    1 (2%)                                             
   Uterus                                             (50)         (50)         (49)         (50)                                   
      Carcinoma                                        1 (2%)                                 1 (2%)                                
      Hemangioma                                                                 1 (2%)                                             
      Hemangiosarcoma                                  1 (2%)                    2 (4%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       3 (6%)                                
      Leiomyoma                                                     1 (2%)       1 (2%)       1 (2%)                                
      Polyp Stromal                                    3 (6%)       2 (4%)       2 (4%)                                             
      Polyp Stromal, Multiple                                       1 (2%)                                                          
      Sarcoma Stromal                                  1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (50)         (50)         (49)         (50)                                   
      Hemangiosarcoma, Metastatic, Spleen              1 (2%)       1 (2%)                                                          
      Histiocytic Sarcoma                              3 (6%)                    1 (2%)       1 (2%)                                
   Lymph Node                                         (7)          (3)          (9)          (5)                                    
      Iliac, Histiocytic Sarcoma                                                 1 (11%)                                            
      Lumbar, Hemangiosarcoma                                                    1 (11%)                                            
      Lumbar, Histiocytic Sarcoma                                                             1 (20%)                               
                                                             Page   4                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - cont                                                                                                         
      Pancreatic, Hepatocholangiocarcinoma,                                                                                         
          Metastatic, Liver                            1 (14%)                                                                      
      Renal, Histiocytic Sarcoma                       1 (14%)                                                                      
   Lymph Node, Bronchial                              (44)         (41)         (39)         (37)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (5%)       1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                 1 (3%)                                
   Lymph Node, Mandibular                             (40)         (42)         (39)         (38)                                   
      Histiocytic Sarcoma                                                        1 (3%)       1 (3%)                                
   Lymph Node, Mesenteric                             (50)         (49)         (49)         (47)                                   
      Hemangiosarcoma, Metastatic, Uterus                                        1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              2 (4%)                    1 (2%)       1 (2%)                                
   Lymph Node, Mediastinal                            (46)         (40)         (38)         (41)                                   
      Carcinoma, Metastatic, Skin                                                1 (3%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)       1 (3%)                                                          
      Histiocytic Sarcoma                              2 (4%)                                 1 (2%)                                
   Spleen                                             (50)         (50)         (49)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       2 (4%)       2 (4%)       1 (2%)                                
      Hemangiosarcoma, Metastatic, Uterus                                        1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       2 (4%)                                
   Thymus                                             (49)         (47)         (46)         (46)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Mammary Gland                                      (50)         (49)         (50)         (49)                                   
      Carcinoma                                        1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Basal Cell Carcinoma                                                       1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Sarcoma                                          1 (2%)                                                                       
      Subcutaneous Tissue, Fibrosarcoma                                          1 (2%)                                             
      Subcutaneous Tissue, Fibrous Histiocytoma        2 (4%)       1 (2%)                    1 (2%)                                
      Subcutaneous Tissue, Hemangioma                                                         1 (2%)                                
      Subcutaneous Tissue, Hemangiosarcoma                                       1 (2%)                                             
      Subcutaneous Tissue, Hemangiosarcoma,                                                                                         
          Metastatic, Spleen                           1 (2%)                                                                       
      Subcutaneous Tissue, Histiocytic Sarcoma         1 (2%)                                                                       
      Subcutaneous Tissue, Liposarcoma                                           1 (2%)                                             
      Subcutaneous Tissue, Sarcoma                     1 (2%)       1 (2%)                    3 (6%)                                
      Subcutaneous Tissue, Sarcoma, Multiple                                                  1 (2%)                                
                                                             Page   5                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Bone                                               (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Skeletal Muscle                                    (1)          (2)          (3)          (2)                                    
      Carcinoma, Metastatic, Skin                                                1 (33%)                                            
      Hemangiosarcoma, Metastatic, Spleen                                        1 (33%)                                            
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (100%)     1 (50%)                                                         
      Histiocytic Sarcoma                                                                     1 (50%)                               
      Sarcoma                                                                    1 (33%)                                            
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   Brain                                              (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Larynx                                             (50)         (50)         (49)         (50)                                   
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     3 (6%)       2 (4%)       1 (2%)       1 (2%)                                
      Alveolar/Bronchiolar Adenoma, Multiple           1 (2%)                                                                       
      Alveolar/Bronchiolar Carcinoma                                2 (4%)       1 (2%)       1 (2%)                                
      Carcinoma, Metastatic, Skin                                                1 (2%)                                             
      Carcinoma, Metastatic, Thyroid Gland             1 (2%)                                                                       
      Hemangiosarcoma, Metastatic, Uterus                                        1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic, Liver      4 (8%)       1 (2%)       1 (2%)       1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)       1 (2%)                                                          
      Histiocytic Sarcoma                              3 (6%)                    1 (2%)       2 (4%)                                
   Nose                                               (50)         (50)         (50)         (49)                                   
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
   Pleura                                                                       (1)                                                 
      Carcinoma, Metastatic, Skin                                                1 (100%)                                           
   Trachea                                            (50)         (50)         (49)         (50)                                   
____________________________________________________________________________________________________________________________________
                                                             Page   6                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Eye                                                (49)         (48)         (49)         (50)                                   
      Histiocytic Sarcoma                                                        1 (2%)                                             
   Harderian Gland                                    (49)         (49)         (49)         (50)                                   
      Adenoma                                          6 (12%)      4 (8%)       2 (4%)       3 (6%)                                
      Carcinoma                                        1 (2%)       3 (6%)       2 (4%)       3 (6%)                                
      Histiocytic Sarcoma                                                        1 (2%)                                             
____________________________________________________________________________________________________________________________________
 URINARY SYSTEM                                                                                                                     
   Kidney                                             (50)         (50)         (49)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)                                                                       
      Histiocytic Sarcoma                              2 (4%)                    1 (2%)       3 (6%)                                
   Urinary Bladder                                    (50)         (50)         (49)         (50)                                   
      Histiocytic Sarcoma                                                        1 (2%)                                             
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              3 (6%)                    1 (2%)       6 (12%)                               
      Lymphoma Malignant                              13 (26%)      5 (10%)     11 (22%)     13 (26%)                               
____________________________________________________________________________________________________________________________________
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   7                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            42          40          40          42                                       
     Total Primary Neoplasms                           75          60          73          84                                       
   Total Animals with Benign Neoplasms                 29          29          30          33                                       
     Total Benign Neoplasms                            37          37          39          40                                       
   Total Animals with Malignant Neoplasms              30          22          28          31                                       
     Total Malignant Neoplasms                         38          23          34          44                                       
   Total Animals with Metastatic Neoplasms              9           3           4           1                                       
     Total Metastatic Neoplasm                         27          19          11           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   8                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 9            6           12            9                                     
    Natural Death                                      1            2            3            4                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                40           42           34           37                                     
    Natural Death                                                                1                                                  
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Intestine Large, Cecum                             (49)         (48)         (47)         (47)                                   
   Intestine Small, Duodenum                          (49)         (48)         (45)         (47)                                   
      Adenoma                                          1 (2%)                    1 (2%)       1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Intestine Small, Jejunum                           (49)         (48)         (47)         (47)                                   
      Adenoma                                                       1 (2%)                                                          
   Intestine Small, Ileum                             (49)         (48)         (48)         (47)                                   
      Carcinoma                                                     1 (2%)                    1 (2%)                                
   Liver                                              (50)         (50)         (50)         (50)                                   
      Fibrous Histiocytoma, Metastatic, Skin                                                  1 (2%)                                
      Hemangioma                                       1 (2%)                                                                       
      Hemangiosarcoma                                  2 (4%)       1 (2%)       2 (4%)                                             
      Hepatoblastoma                                                1 (2%)                                                          
      Hepatocellular Carcinoma                        10 (20%)     11 (22%)      8 (16%)      7 (14%)                               
      Hepatocellular Carcinoma, Multiple               2 (4%)       1 (2%)       2 (4%)       2 (4%)                                
      Hepatocellular Adenoma                          11 (22%)     14 (28%)     11 (22%)     19 (38%)                               
      Hepatocellular Adenoma, Multiple                 6 (12%)     11 (22%)     12 (24%)     15 (30%)                               
      Hepatocholangiocarcinoma                         5 (10%)      2 (4%)                                                          
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       1 (2%)                                
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
   Mesentery                                          (9)          (3)          (3)          (4)                                    
      Sarcoma, Metastatic, Salivary Glands                                                    1 (25%)                               
   Pancreas                                           (49)         (50)         (49)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver                                1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)                                                                       
      Histiocytic Sarcoma                                                        1 (2%)                                             
   Salivary Glands                                    (50)         (50)         (48)         (50)                                   
      Sarcoma                                                                                 1 (2%)                                
                                                             Page   9                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM - cont                                                                                                            
   Stomach, Forestomach                               (50)         (49)         (49)         (50)                                   
      Squamous Cell Carcinoma                                                                 1 (2%)                                
      Squamous Cell Papilloma                                                                 1 (2%)                                
   Stomach, Glandular                                 (49)         (49)         (49)         (49)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)       2 (4%)                                                          
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (50)         (50)         (49)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)                                                                       
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
      Capsule, Adenoma                                 2 (4%)                    1 (2%)       1 (2%)                                
   Adrenal Medulla                                    (50)         (50)         (49)         (50)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                                                                       
      Ganglioneuroma                                                             1 (2%)                                             
      Pheochromocytoma Malignant                       1 (2%)                                                                       
   Islets, Pancreatic                                 (49)         (50)         (49)         (50)                                   
      Adenoma                                          1 (2%)       1 (2%)                    3 (6%)                                
   Pituitary Gland                                    (50)         (47)         (48)         (49)                                   
      Astrocytoma Malignant, Metastatic, Brain                                   1 (2%)                                             
      Histiocytic Sarcoma                                                        1 (2%)                                             
      Pars Distalis, Adenoma                                                                  1 (2%)                                
   Thyroid Gland                                      (50)         (49)         (50)         (50)                                   
      Follicular Cell, Adenoma                                      1 (2%)                                                          
      Follicular Cell, Carcinoma                                    1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                             Page  10                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
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         B6C3F1 MICE MALE                          CONTROL      450 PPM      900 PPM      1800 PPM                                  
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 GENITAL SYSTEM                                                                                                                     
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Prostate                                           (50)         (49)         (49)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
   Seminal Vesicle                                    (50)         (50)         (49)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Testes                                             (50)         (50)         (50)         (50)                                   
      Interstitial Cell, Adenoma                                    2 (4%)                                                          
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 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (50)         (49)         (50)         (49)                                   
      Fibrous Histiocytoma, Metastatic, Skin                                                  1 (2%)                                
      Hemangiosarcoma                                                                         1 (2%)                                
   Lymph Node                                                                   (1)          (2)                                    
   Lymph Node, Bronchial                              (39)         (35)         (37)         (39)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (3%)       2 (6%)                                                          
      Sarcoma, Metastatic, Bone                        1 (3%)                                                                       
   Lymph Node, Mandibular                             (37)         (36)         (32)         (34)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (3%)                                                                       
      Histiocytic Sarcoma                                                        1 (3%)                                             
      Sarcoma, Metastatic, Salivary Glands                                                    1 (3%)                                
   Lymph Node, Mesenteric                             (49)         (48)         (48)         (48)                                   
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
   Lymph Node, Mediastinal                            (42)         (38)         (36)         (38)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      3 (7%)       2 (5%)                                                          
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
   Spleen                                             (50)         (50)         (49)         (49)                                   
      Hemangiosarcoma                                  1 (2%)                                                                       
      Histiocytic Sarcoma                                                        1 (2%)                                             
   Thymus                                             (42)         (44)         (44)         (47)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)       1 (2%)                                                          
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
      Thymoma Malignant                                1 (2%)                                                                       
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                                                             Page  11                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      450 PPM      900 PPM      1800 PPM                                  
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 INTEGUMENTARY SYSTEM                                                                                                               
   Skin                                               (50)         (50)         (49)         (50)                                   
      Subcutaneous Tissue, Fibrosarcoma                                                       1 (2%)                                
      Subcutaneous Tissue, Fibrous Histiocytoma        1 (2%)                                 1 (2%)                                
      Subcutaneous Tissue, Hemangiosarcoma                                       1 (2%)                                             
      Subcutaneous Tissue, Histiocytic Sarcoma                                   1 (2%)                                             
      Subcutaneous Tissue, Sarcoma, Metastatic,                                                                                     
           Bone                                        1 (2%)                                                                       
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 MUSCULOSKELETAL SYSTEM                                                                                                             
   Bone                                               (50)         (50)         (50)         (50)                                   
      Sarcoma                                          1 (2%)                                                                       
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
   Skeletal Muscle                                    (3)          (2)                                                              
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (67%)      2 (100%)                                                        
      Sarcoma, Metastatic, Bone                        1 (33%)                                                                      
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 NERVOUS SYSTEM                                                                                                                     
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                                      1 (2%)                                             
      Histiocytic Sarcoma                                                        1 (2%)                                             
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 RESPIRATORY SYSTEM                                                                                                                 
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     8 (16%)      5 (10%)      1 (2%)       5 (10%)                               
      Alveolar/Bronchiolar Adenoma, Multiple           1 (2%)                                                                       
      Alveolar/Bronchiolar Carcinoma                   5 (10%)      1 (2%)       3 (6%)       4 (8%)                                
      Alveolar/Bronchiolar Carcinoma, Multiple                                                1 (2%)                                
      Carcinoma, Metastatic, Harderian Gland                        1 (2%)                                                          
      Hepatocellular Carcinoma, Metastatic, Liver      7 (14%)      5 (10%)      3 (6%)       5 (10%)                               
      Hepatocholangiocarcinoma, Metastatic, Liver      3 (6%)       2 (4%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
      Sarcoma, Metastatic, Salivary Glands                                                    1 (2%)                                
   Nose                                               (50)         (50)         (50)         (50)                                   
      Fibrous Histiocytoma, Metastatic, Skin                                                  1 (2%)                                
      Histiocytic Sarcoma                                                        1 (2%)                                             
                                                             Page  12                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
RESPIRATORY SYSTEM - cont                                                                                                           
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
   Pleura                                             (1)                                                                           
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (100%)                                                                     
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 SPECIAL SENSES SYSTEM                                                                                                              
   Eye                                                (49)         (48)         (49)         (49)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Harderian Gland                                    (50)         (49)         (50)         (50)                                   
      Adenoma                                          5 (10%)      4 (8%)       5 (10%)      7 (14%)                               
      Carcinoma                                        2 (4%)       1 (2%)       1 (2%)       2 (4%)                                
      Histiocytic Sarcoma                                                        1 (2%)                                             
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 URINARY SYSTEM                                                                                                                     
   Kidney                                             (50)         (50)         (49)         (50)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                                                                       
      Fibrous Histiocytoma, Metastatic, Skin                                                  1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sarcoma, Metastatic, Bone                        1 (2%)                                                                       
      Renal Tubule, Carcinoma                                       1 (2%)                                                          
   Ureter                                                                                    (1)                                    
      Transitional Epithelium, Carcinoma                                                      1 (100%)                              
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 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       1 (2%)                                
      Lymphoma Malignant                               1 (2%)       3 (6%)       1 (2%)       2 (4%)                                
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     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  13                                                               
NTP Experiment-Test: 97006-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                       METHYL ISOBUTYL KETONE                                  Date: 04/29/04  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 07:47:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      450 PPM      900 PPM      1800 PPM                                  
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            45          41          36          45                                       
     Total Primary Neoplasms                           69          63          52          79                                       
   Total Animals with Benign Neoplasms                 27          32          29          37                                       
     Total Benign Neoplasms                            36          39          32          53                                       
   Total Animals with Malignant Neoplasms              29          21          16          20                                       
     Total Malignant Neoplasms                         33          24          20          26                                       
   Total Animals with Metastatic Neoplasms             12           8           4           7                                       
     Total Metastatic Neoplasm                         46          19           5          12                                       
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
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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  14                                                               
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