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TDMS Study 60968-02 Pathology Tables

NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28

                                                           CORE STUDY




       Facility:  Battelle Northwest

       Chemical CAS #:  0078-84-2

       Lock Date:  05/12/94

       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: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                16           13           11           11                                     
    Natural Death                                      5            4            3            2                                     
    Accidently Killed                                  1            1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                28           32           35           37                                     
    Natural Death                                                                1                                                  
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (46)         (44)         (45)         (47)                                   
   Intestine Large, Rectum                            (50)         (49)         (49)         (49)                                   
   Intestine Large, Cecum                             (49)         (46)         (49)         (50)                                   
      Leiomyoma                                                     1 (2%)                                                          
   Intestine Small, Duodenum                          (47)         (45)         (47)         (48)                                   
      Polyp Adenomatous                                             1 (2%)                                                          
   Intestine Small, Jejunum                           (47)         (46)         (48)         (49)                                   
      Carcinoma                                                                  1 (2%)                                             
   Intestine Small, Ileum                             (49)         (46)         (47)         (49)                                   
   Liver                                              (49)         (49)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       1 (2%)                                                          
      Hepatocellular Carcinoma                         6 (12%)      8 (16%)      4 (8%)       3 (6%)                                
      Hepatocellular Carcinoma, Multiple                            1 (2%)                                                          
      Hepatocellular Adenoma                           6 (12%)     12 (24%)      9 (18%)      8 (16%)                               
      Hepatocellular Adenoma, Multiple                 3 (6%)                    2 (4%)       1 (2%)                                
      Hepatocholangiocarcinoma                         2 (4%)       1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
   Mesentery                                          (8)          (2)          (4)          (3)                                    
      Hemangiosarcoma                                  1 (13%)                                                                      
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (25%)                                                                      
      Histiocytic Sarcoma                                                        1 (25%)                                            
      Leiomyosarcoma, Metastatic, Uterus                                         1 (25%)                                            
   Pancreas                                           (50)         (49)         (50)         (50)                                   
      Carcinoma                                                                  1 (2%)                                             
      Hemangiosarcoma                                                            1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
   Salivary Glands                                    (50)         (50)         (49)         (50)                                   
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
                                                             Page   2                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - cont                                                                                                            
      Squamous Cell Papilloma                                                    3 (6%)       1 (2%)                                
   Stomach, Glandular                                 (49)         (49)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Tongue                                                                       (1)                                                 
      Squamous Cell Carcinoma                                                    1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (49)         (50)         (50)                                   
      Adenoma                                                       1 (2%)                                                          
      Hepatocellular Carcinoma, Metastatic, Liver                                             1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                                                        1 (2%)                                             
      Capsule, Adenoma                                              1 (2%)                                                          
   Adrenal Medulla                                    (50)         (49)         (50)         (50)                                   
      Pheochromocytoma Malignant                                                              1 (2%)                                
      Pheochromocytoma Benign                          1 (2%)       2 (4%)                                                          
   Islets, Pancreatic                                 (50)         (49)         (50)         (50)                                   
      Adenoma                                          1 (2%)       1 (2%)       1 (2%)                                             
      Carcinoma                                                                  2 (4%)                                             
   Pituitary Gland                                    (50)         (49)         (50)         (49)                                   
      Pars Distalis, Adenoma                          10 (20%)      9 (18%)      6 (12%)      9 (18%)                               
      Pars Intermedia, Adenoma                                                   1 (2%)       1 (2%)                                
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Follicular Cell, Adenoma                         3 (6%)       1 (2%)       2 (4%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Ovary                                              (50)         (49)         (50)         (50)                                   
      Choriocarcinoma                                               1 (2%)                                                          
      Cystadenocarcinoma                                            2 (4%)                                                          
      Cystadenoma                                      1 (2%)       5 (10%)                   2 (4%)                                
      Hemangiosarcoma                                                                         1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
                                                             Page   3                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - cont                                                                                                               
      Luteoma                                                       1 (2%)       1 (2%)       1 (2%)                                
      Teratoma Benign                                  1 (2%)                                                                       
      Teratoma Malignant                               1 (2%)                                                                       
      Tubulostromal Adenoma                            1 (2%)                                                                       
      Yolk Sac Carcinoma                               1 (2%)                                                                       
      Bilateral, Cystadenoma                                                     1 (2%)                                             
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                    2 (4%)                                             
      Leiomyosarcoma                                                             1 (2%)                                             
      Polyp Stromal                                    2 (4%)       2 (4%)       1 (2%)       5 (10%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                               1 (2%)       1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node                                         (5)          (5)          (4)          (4)                                    
      Iliac, Histiocytic Sarcoma                       1 (20%)                   1 (25%)                                            
      Renal, Hemangiosarcoma                                        1 (20%)                                                         
      Renal, Histiocytic Sarcoma                       1 (20%)                                                                      
   Lymph Node, Bronchial                              (42)         (38)         (42)         (44)                                   
   Lymph Node, Mandibular                             (38)         (38)         (44)         (45)                                   
      Histiocytic Sarcoma                              1 (3%)                                                                       
   Lymph Node, Mesenteric                             (48)         (49)         (47)         (47)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node, Mediastinal                            (38)         (38)         (38)         (38)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (5%)                                                                       
      Histiocytic Sarcoma                              1 (3%)                                                                       
   Spleen                                             (50)         (49)         (50)         (50)                                   
      Hemangiosarcoma                                               1 (2%)       1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)                                                                       
   Thymus                                             (41)         (43)         (41)         (43)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (49)         (50)         (50)         (50)                                   
      Carcinoma                                        1 (2%)       1 (2%)       2 (4%)                                             
   Skin                                               (50)         (50)         (50)         (50)                                   
      Squamous Cell Carcinoma                                                                 1 (2%)                                
      Subcutaneous Tissue, Fibrosarcoma                             1 (2%)                    2 (4%)                                
      Subcutaneous Tissue, Hemangiosarcoma                          2 (4%)       1 (2%)                                             
      Subcutaneous Tissue, Histiocytic Sarcoma                                   1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                             Page   4                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                                 (1)          (1)                                                 
      Fibrosarcoma                                                               1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (49)         (50)                                   
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                  1 (2%)       1 (2%)       3 (6%)                                
      Alveolar/Bronchiolar Carcinoma                   3 (6%)                    2 (4%)       1 (2%)                                
      Carcinoma, Metastatic, Harderian Gland                                     1 (2%)                                             
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)       1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic, Liver      2 (4%)       2 (4%)       1 (2%)       1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver      2 (4%)       1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
      Squamous Cell Carcinoma, Metastatic, Skin                                               1 (2%)                                
      Mediastinum, Hepatocholangiocarcinoma,                                                                                        
          Metastatic, Liver                            1 (2%)                                                                       
   Nose                                               (50)         (50)         (50)         (50)                                   
      Hemangioma                                                                 1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Harderian Gland                                    (3)          (4)          (2)          (2)                                    
      Adenoma                                          1 (33%)      4 (100%)     1 (50%)      1 (50%)                               
      Carcinoma                                        1 (33%)                   1 (50%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Ureter                                                                       (1)                                                 
      Transitional Epithelium, Papilloma                                         1 (100%)                                           
   Urinary Bladder                                    (49)         (49)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)                                             
                                                             Page   5                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - cont                                                                                                               
      Leiomyosarcoma, Metastatic, Uterus                                         1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                    3 (6%)       1 (2%)                                
      Lymphoma Malignant                              12 (24%)     13 (26%)     12 (24%)     19 (38%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   6                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            38          45          37          40                                       
     Total Primary Neoplasms                           60          76          66          62                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 26          34          26          25                                       
     Total Benign Neoplasms                            30          42          31          33                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              25          28          26          24                                       
     Total Malignant Neoplasms                         30          34          35          29                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              4           4           3           2                                       
     Total Metastatic Neoplasm                         16           4           5           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                                                                              
                                                             Page   7                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 6            8            6           15                                     
    Natural Death                                      4            5            9            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                40           37           35           30                                     
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (49)         (49)         (50)         (49)                                   
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
   Intestine Large, Cecum                             (49)         (48)         (48)         (48)                                   
      Leiomyoma                                        1 (2%)                                                                       
   Intestine Small, Jejunum                           (49)         (49)         (48)         (46)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Intestine Small, Ileum                             (49)         (49)         (47)         (48)                                   
   Liver                                              (49)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
      Cholangioma                                      1 (2%)                                                                       
      Hemangiosarcoma                                  1 (2%)                                                                       
      Hepatocellular Carcinoma                        14 (29%)     12 (24%)      9 (18%)      8 (16%)                               
      Hepatocellular Carcinoma, Multiple               3 (6%)       2 (4%)       3 (6%)       5 (10%)                               
      Hepatocellular Adenoma                           8 (16%)     13 (26%)     14 (28%)      6 (12%)                               
      Hepatocellular Adenoma, Multiple                 4 (8%)       1 (2%)       1 (2%)       1 (2%)                                
      Hepatocholangiocarcinoma                                      1 (2%)                                                          
   Mesentery                                          (1)          (3)          (5)          (3)                                    
      Hepatocellular Carcinoma, Metastatic, Liver                                             1 (33%)                               
      Artery, Fibrous Histiocytoma                                               1 (20%)                                            
   Pancreas                                           (50)         (49)         (50)         (50)                                   
      Artery, Fibrous Histiocytoma                                               1 (2%)                                             
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Squamous Cell Papilloma                          1 (2%)                    1 (2%)                                             
   Stomach, Glandular                                 (50)         (50)         (49)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Artery, Fibrous Histiocytoma                                               1 (2%)                                             
   Tooth                                                           (3)          (2)                                                 
      Odontoma                                                                   1 (50%)                                            
____________________________________________________________________________________________________________________________________
                                                             Page   8                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)       1 (2%)                                                          
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
      Capsule, Adenoma                                 1 (2%)                    1 (2%)       1 (2%)                                
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Pheochromocytoma Benign                                       1 (2%)                    1 (2%)                                
   Islets, Pancreatic                                 (50)         (49)         (50)         (50)                                   
      Adenoma                                          1 (2%)                    1 (2%)       1 (2%)                                
   Parathyroid Gland                                  (43)         (41)         (45)         (42)                                   
      Carcinoma                                                                               1 (2%)                                
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      C-Cell, Carcinoma                                                          1 (2%)                                             
      Follicular Cell, Adenoma                         3 (6%)       2 (4%)       1 (2%)       5 (10%)                               
      Follicular Cell, Carcinoma                       1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Leiomyoma                                                                               1 (2%)                                
   Seminal Vesicle                                    (50)         (50)         (50)         (50)                                   
      Carcinoma                                        1 (2%)                                                                       
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
   Testes                                             (50)         (50)         (50)         (50)                                   
      Interstitial Cell, Adenoma                                                              1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
      Hemangiosarcoma                                  1 (2%)                    1 (2%)                                             
   Lymph Node                                                                                (4)                                    
   Lymph Node, Bronchial                              (37)         (34)         (33)         (34)                                   
   Lymph Node, Mandibular                             (27)         (25)         (36)         (31)                                   
                                                             Page   9                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - cont                                                                                                         
   Lymph Node, Mesenteric                             (50)         (48)         (47)         (47)                                   
   Lymph Node, Mediastinal                            (29)         (34)         (28)         (34)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                                  1 (4%)                                             
      Fibrosarcoma, Metastatic, Skin                   1 (3%)                                                                       
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       2 (4%)       1 (2%)                                             
   Thymus                                             (39)         (39)         (42)         (36)                                   
      Fibrous Histiocytoma                                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (49)         (50)         (50)         (50)                                   
      Fibrous Histiocytoma                                                       1 (2%)                                             
      Mast Cell Tumor Benign                                                     1 (2%)                                             
      Squamous Cell Carcinoma                                       1 (2%)                                                          
      Squamous Cell Papilloma                                                    1 (2%)                                             
      Subcutaneous Tissue, Fibrosarcoma                1 (2%)                                                                       
      Subcutaneous Tissue, Hemangiosarcoma                                                    1 (2%)                                
      Subcutaneous Tissue, Sarcoma                     1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                                            1 (2%)                                             
   Skeletal Muscle                                                              (1)                                                 
      Hemangiosarcoma                                                            1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     5 (10%)      2 (4%)       6 (12%)      4 (8%)                                
      Alveolar/Bronchiolar Adenoma, Multiple                        1 (2%)                    1 (2%)                                
      Alveolar/Bronchiolar Carcinoma                   6 (12%)      6 (12%)      3 (6%)       6 (12%)                               
      Alveolar/Bronchiolar Carcinoma, Multiple         1 (2%)                    1 (2%)                                             
      Carcinoma, Metastatic, Harderian Gland                                     1 (2%)                                             
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
                                                             Page  10                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - cont                                                                                                           
      Carcinoma, Metastatic, Thyroid Gland             1 (2%)                    1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic, Liver                   4 (8%)       4 (8%)       5 (10%)                               
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
      Artery, Fibrous Histiocytoma                                               1 (2%)                                             
      Artery, Mediastinum, Fibrous Histiocytoma                                  1 (2%)                                             
      Mediastinum, Alveolar/Bronchiolar Carcinoma,                                                                                  
           Metastatic, Lung                            1 (2%)                    1 (2%)                                             
      Mediastinum, Fibrosarcoma, Metastatic, Skin      1 (2%)                                                                       
      Mediastinum, Hepatocholangiocarcinoma,                                                                                        
          Metastatic, Liver                                         1 (2%)                                                          
   Nose                                               (50)         (50)         (50)         (50)                                   
      Vomeronasal Organ, Adenoma                       1 (2%)                                                                       
   Trachea                                            (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Harderian Gland                                    (3)          (2)          (3)          (2)                                    
      Adenoma                                          1 (33%)                   1 (33%)      2 (100%)                              
      Carcinoma                                        2 (67%)      2 (100%)     1 (33%)                                            
      Sarcoma                                                                    1 (33%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
      Hepatocellular Carcinoma, Metastatic, Liver                                             1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Urinary Bladder                                    (50)         (50)         (48)         (50)                                   
      Carcinoma, Metastatic, Parathyroid Gland                                                1 (2%)                                
      Artery, Fibrous Histiocytoma                                               1 (2%)                                             
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Lymphoma Malignant                               1 (2%)       5 (10%)      1 (2%)       6 (12%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  11                                                               
NTP Experiment-Test: 60968-02  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          ISOBUTYRALDEHYDE                                     Date: 09/23/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:37:28  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      500 PPM      1000 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            40          36          39          34                                       
     Total Primary Neoplasms                           62          52          63          51                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 22          19          22          19                                       
     Total Benign Neoplasms                            28          21          29          24                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              28          27          22          25                                       
     Total Malignant Neoplasms                         34          31          34          27                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              4           5           7           7                                       
     Total Metastatic Neoplasm                          6           9           8          16                                       
                                                                                                                                    
   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  12                                                               
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