https://ntp.niehs.nih.gov/go/17669

TDMS Study 88004-06 Pathology Tables

NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09
                                                         FINAL #1 MICE
       Facility:  Battelle Northwest
       Chemical CAS #:  1321-74-0
       Lock Date:  06/17/02
       Cage Range:  All
       Reasons For Removal:    All
       Removal Date Range:     All
       Treatment Groups:       Include All
a  Number of animals examined microscopically at site and number of animals with lesion
                                                              Page   1
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                11           12            8            7                                     
    Natural Death                                      6            3            3            1                                     
    Accidently Killed                                                            1                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                33           35           38           42                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Gallbladder                                        (45)         (41)         (36)         (41)                                   
   Intestine Large, Colon                             (48)         (50)         (50)         (50)                                   
   Intestine Large, Cecum                             (47)         (49)         (48)         (50)                                   
   Intestine Small, Duodenum                          (46)         (48)         (48)         (49)                                   
      Carcinoma                                                                  1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Intestine Small, Jejunum                           (46)         (48)         (48)         (49)                                   
      Carcinoma                                                     2 (4%)                                                          
   Liver                                              (49)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma                         3 (6%)       4 (8%)       3 (6%)       2 (4%)                                
      Hepatocellular Carcinoma, Multiple               2 (4%)                                                                       
      Hepatocellular Adenoma                          12 (24%)      4 (8%)       5 (10%)      4 (8%)                                
      Hepatocellular Adenoma, Multiple                 5 (10%)      3 (6%)       1 (2%)       1 (2%)                                
      Hepatocholangiocarcinoma                         1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Mesentery                                          (17)         (16)         (4)          (5)                                    
   Pancreas                                           (48)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
   Stomach, Glandular                                 (49)         (50)         (49)         (49)                                   
      Adenoma                                          1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                             Page   2                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Mammary Gland                                                    1 (2%)                                
      Sarcoma                                                       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Adrenal Medulla                                    (49)         (50)         (49)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Pheochromocytoma Malignant                                                              2 (4%)                                
      Pheochromocytoma Benign                                                    1 (2%)                                             
   Islets, Pancreatic                                 (48)         (49)         (49)         (50)                                   
      Carcinoma                                        1 (2%)                                                                       
   Pituitary Gland                                    (47)         (50)         (49)         (45)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Pars Distalis, Adenoma                           8 (17%)      8 (16%)      1 (2%)       1 (2%)                                
      Pars Intermedia, Adenoma                         1 (2%)                                                                       
   Thyroid Gland                                      (49)         (49)         (50)         (48)                                   
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Ovary                                              (48)         (50)         (49)         (49)                                   
      Cystadenoma                                      3 (6%)                                 1 (2%)                                
      Hemangioma                                                                              1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Luteoma                                          1 (2%)                                                                       
   Uterus                                             (49)         (50)         (50)         (49)                                   
      Adenoma                                                                                 1 (2%)                                
      Carcinoma                                                                               1 (2%)                                
      Fibroma                                                       1 (2%)                                                          
      Histiocytic Sarcoma                                                        2 (4%)                                             
      Polyp Stromal                                    1 (2%)       3 (6%)                    2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                             Page   3                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (49)         (49)         (50)         (50)                                   
      Hemangiosarcoma                                               2 (4%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sarcoma, Metastatic, Skin                                                  1 (2%)                                             
   Lymph Node                                         (9)          (3)          (5)          (2)                                    
      Renal, Carcinoma, Metastatic, Mammary Gland                                             1 (50%)                               
   Lymph Node, Bronchial                              (43)         (46)         (39)         (39)                                   
   Lymph Node, Mandibular                             (41)         (45)         (44)         (41)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node, Mesenteric                             (49)         (50)         (49)         (49)                                   
      Carcinoma, Metastatic, Mammary Gland                                                    1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node, Mediastinal                            (44)         (44)         (38)         (38)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                                               1 (3%)                                
      Carcinoma, Metastatic, Mammary Gland                                                    1 (3%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver                                             1 (3%)                                
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Spleen                                             (49)         (50)         (49)         (49)                                   
      Hemangiosarcoma                                               3 (6%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Thymus                                             (49)         (47)         (46)         (44)                                   
      Carcinoma, Metastatic, Mammary Gland                                                    1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Mammary Gland                                      (50)         (49)         (50)         (49)                                   
      Carcinoma                                                     2 (4%)                                                          
      Carcinoma, Multiple                                                                     1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Squamous Cell Papilloma                          1 (2%)                                                                       
      Subcutaneous Tissue, Hemangiosarcoma             1 (2%)       1 (2%)                                                          
      Subcutaneous Tissue, Neural Crest Tumor          1 (2%)                                                                       
      Subcutaneous Tissue, Sarcoma                     1 (2%)       1 (2%)       2 (4%)       1 (2%)                                
      Subcutaneous Tissue, Sarcoma, Multiple                        1 (2%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                             Page   4                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Bone                                               (50)         (50)         (50)         (50)                                   
      Osteoma                                                       1 (2%)                                                          
      Osteosarcoma                                                               1 (2%)                                             
   Skeletal Muscle                                                 (1)                       (1)                                    
      Carcinoma, Metastatic, Mammary Gland                                                    1 (100%)                              
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   Brain                                              (50)         (50)         (50)         (50)                                   
      Meningioma Benign                                                          1 (2%)                                             
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Larynx                                             (48)         (50)         (50)         (49)                                   
   Lung                                               (50)         (50)         (50)         (49)                                   
      Alveolar/Bronchiolar Adenoma                     4 (8%)       9 (18%)      4 (8%)       6 (12%)                               
      Alveolar/Bronchiolar Adenoma, Multiple                                                  2 (4%)                                
      Alveolar/Bronchiolar Carcinoma                   2 (4%)       3 (6%)       4 (8%)       5 (10%)                               
      Alveolar/Bronchiolar Carcinoma, Multiple                      2 (4%)                                                          
      Carcinoma, Metastatic, Mammary Gland                                                    1 (2%)                                
      Hemangiosarcoma, Metastatic, Spleen                           1 (2%)                                                          
      Hepatocellular Carcinoma, Metastatic, Liver      3 (6%)       2 (4%)                    1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sarcoma, Metastatic, Skin                                     2 (4%)       1 (2%)                                             
   Nose                                               (50)         (50)         (50)         (49)                                   
      Hemangioma                                       1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Olfactory Epithelium, Neuroblastoma                                                     1 (2%)                                
   Trachea                                            (49)         (50)         (50)         (50)                                   
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Eye                                                (50)         (50)         (50)         (49)                                   
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Adenoma                                          4 (8%)       1 (2%)       4 (8%)       5 (10%)                               
      Carcinoma                                        2 (4%)       4 (8%)       1 (2%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                             Page   5                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
 URINARY SYSTEM                                                                                                                     
   Kidney                                             (49)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Mammary Gland                                                    1 (2%)                                
      Hepatocellular Carcinoma, Metastatic, Liver                                             1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Renal Tubule, Adenoma                                                                   1 (2%)                                
   Urinary Bladder                                    (49)         (50)         (50)         (49)                                   
____________________________________________________________________________________________________________________________________
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                    2 (4%)                                             
      Lymphoma Malignant                              11 (22%)     10 (20%)      5 (10%)      1 (2%)                                
____________________________________________________________________________________________________________________________________
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   6                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            40          40          26          26                                       
     Total Primary Neoplasms                           68          66          37          41                                       
   Total Animals with Benign Neoplasms                 28          21          14          19                                       
     Total Benign Neoplasms                            42          30          17          25                                       
   Total Animals with Malignant Neoplasms              22          29          19          13                                       
     Total Malignant Neoplasms                         25          36          20          16                                       
   Total Animals with Metastatic Neoplasms              4           5           2           2                                       
     Total Metastatic Neoplasm                          4           6           2          12                                       
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                  1                                                                           
     Total Uncertain Neoplasms                          1                                                                           
____________________________________________________________________________________________________________________________________
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: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 7            6            5            4                                     
    Natural Death                                      2            6            3            3                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                41           38           42           43                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Gallbladder                                        (42)         (34)         (42)         (45)                                   
      Adenoma                                          1 (2%)                                                                       
   Intestine Large, Rectum                            (48)         (45)         (46)         (47)                                   
      Leiomyosarcoma                                                1 (2%)                                                          
   Intestine Large, Cecum                             (48)         (46)         (47)         (48)                                   
      Carcinoma                                                     1 (2%)                                                          
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Leiomyoma                                                                               1 (2%)                                
      Polyp Adenomatous                                1 (2%)                                                                       
   Intestine Small, Duodenum                          (48)         (45)         (47)         (47)                                   
      Carcinoma                                                     1 (2%)                                                          
   Intestine Small, Jejunum                           (48)         (45)         (47)         (47)                                   
      Carcinoma                                        3 (6%)                                 4 (9%)                                
   Intestine Small, Ileum                             (48)         (45)         (47)         (47)                                   
      Carcinoma                                                                               1 (2%)                                
   Liver                                              (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Pancreas                                            1 (2%)                                             
      Cholangiocarcinoma                                            1 (2%)                                                          
      Hemangiosarcoma                                  3 (6%)       1 (2%)                                                          
      Hepatoblastoma                                                             2 (4%)                                             
      Hepatocellular Carcinoma                        12 (24%)      9 (18%)      7 (14%)      7 (14%)                               
      Hepatocellular Carcinoma, Multiple               1 (2%)       2 (4%)       2 (4%)       3 (6%)                                
      Hepatocellular Adenoma                          10 (20%)     12 (24%)     10 (20%)     11 (22%)                               
      Hepatocellular Adenoma, Multiple                12 (24%)      5 (10%)      2 (4%)       1 (2%)                                
      Hepatocholangiocarcinoma                         1 (2%)       1 (2%)                                                          
      Histiocytic Sarcoma                                                                     1 (2%)                                
   Oral Mucosa                                        (1)                                                                           
      Pharyngeal, Squamous Cell Carcinoma              1 (100%)                                                                     
   Pancreas                                           (49)         (48)         (50)         (50)                                   
                                                             Page   8                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM - cont                                                                                                            
      Carcinoma                                                                  1 (2%)                                             
   Stomach, Forestomach                               (49)         (50)         (49)         (50)                                   
      Squamous Cell Carcinoma                                                                 1 (2%)                                
      Squamous Cell Papilloma                          1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
   Stomach, Glandular                                 (48)         (48)         (47)         (49)                                   
      Carcinoma                                                                  1 (2%)                                             
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (49)         (50)         (50)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                                               1 (2%)                                
      Cholangiocarcinoma, Metastatic, Liver                         1 (2%)                                                          
      Hemangiosarcoma                                  2 (4%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (49)         (49)         (50)         (50)                                   
      Adenoma                                                       1 (2%)                                                          
      Capsule, Adenoma                                 3 (6%)                                                                       
   Adrenal Medulla                                    (49)         (49)         (50)         (50)                                   
      Pheochromocytoma Malignant                                                 1 (2%)                                             
      Pheochromocytoma Benign                          2 (4%)                                                                       
   Islets, Pancreatic                                 (49)         (48)         (50)         (50)                                   
      Adenoma                                          1 (2%)                                                                       
   Thyroid Gland                                      (49)         (49)         (50)         (50)                                   
      Follicular Cell, Adenoma                                      1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                             Page   9                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Sarcoma                                          1 (2%)                                                                       
   Testes                                             (50)         (50)         (50)         (50)                                   
      Hemangioma                                                    1 (2%)                                                          
      Interstitial Cell, Adenoma                       1 (2%)       2 (4%)                    1 (2%)                                
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (50)         (48)         (50)         (50)                                   
      Hemangiosarcoma                                  2 (4%)       1 (2%)                                                          
      Mast Cell Tumor Malignant                        1 (2%)                                                                       
   Lymph Node                                                      (2)          (1)                                                 
      Iliac, Leiomyosarcoma, Metastatic, Intestine                                                                                  
          Large, Rectum                                             1 (50%)                                                         
      Pancreatic, Hepatocholangiocarcinoma,                                                                                         
          Metastatic, Liver                                         1 (50%)                                                         
   Lymph Node, Bronchial                              (35)         (34)         (33)         (37)                                   
      Cholangiocarcinoma, Metastatic, Liver                         1 (3%)                                                          
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (3%)                                                          
      Histiocytic Sarcoma                              1 (3%)                                                                       
   Lymph Node, Mandibular                             (39)         (27)         (35)         (38)                                   
   Lymph Node, Mesenteric                             (44)         (46)         (47)         (50)                                   
      Carcinoma, Metastatic, Pancreas                                            1 (2%)                                             
      Hemangiosarcoma                                  1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (2%)                                                          
   Lymph Node, Mediastinal                            (37)         (38)         (33)         (29)                                   
      Carcinoma, Metastatic, Pancreas                                            1 (3%)                                             
      Carcinoma, Metastatic, Intestine Small,                                                                                       
          Duodenum                                                  1 (3%)                                                          
      Cholangiocarcinoma, Metastatic, Liver                         1 (3%)                                                          
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (3%)                                                          
      Histiocytic Sarcoma                              1 (3%)                                                                       
      Mast Cell Tumor Malignant, Metastatic, Bone                                                                                   
          Marrow                                       1 (3%)                                                                       
      Sarcoma, Metastatic, Skin                        1 (3%)                                                                       
   Spleen                                             (49)         (48)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       2 (4%)                                                          
      Mast Cell Tumor Malignant, Metastatic, Bone                                                                                   
          Marrow                                       1 (2%)                                                                       
      Squamous Cell Carcinoma, Metastatic, Stomach,                                                                                 
                                                             Page  10                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - cont                                                                                                         
           Forestomach                                                                        1 (2%)                                
   Thymus                                             (44)         (41)         (43)         (44)                                   
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Skin                                               (50)         (50)         (50)         (50)                                   
      Subcutaneous Tissue, Fibrous Histiocytoma        2 (4%)                    1 (2%)                                             
      Subcutaneous Tissue, Hemangioma                               1 (2%)                    1 (2%)                                
      Subcutaneous Tissue, Sarcoma                     1 (2%)       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Skeletal Muscle                                                 (2)                                                              
      Cholangiocarcinoma, Metastatic, Liver                         1 (50%)                                                         
      Hepatocholangiocarcinoma, Metastatic, Liver                   1 (50%)                                                         
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Lung                                               (49)         (49)         (49)         (49)                                   
      Alveolar/Bronchiolar Adenoma                    10 (20%)      5 (10%)      6 (12%)     13 (27%)                               
      Alveolar/Bronchiolar Adenoma, Multiple           2 (4%)       1 (2%)                    2 (4%)                                
      Alveolar/Bronchiolar Carcinoma                   5 (10%)      4 (8%)       2 (4%)       8 (16%)                               
      Alveolar/Bronchiolar Carcinoma, Multiple                                   1 (2%)       1 (2%)                                
      Carcinoma, Metastatic, Pancreas                                            1 (2%)                                             
      Cholangiocarcinoma, Metastatic, Liver                         1 (2%)                                                          
      Fibroma                                                                                 1 (2%)                                
      Hemangiosarcoma, Metastatic, Liver               1 (2%)       1 (2%)                                                          
      Hepatocellular Carcinoma, Metastatic, Liver      6 (12%)      5 (10%)      3 (6%)       1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)       1 (2%)                                                          
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Mast Cell Tumor Malignant, Metastatic, Bone                                                                                   
          Marrow                                       1 (2%)                                                                       
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
      Bronchus, Adenoma                                                                       1 (2%)                                
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                                                             Page  11                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
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         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Harderian Gland                                    (50)         (49)         (50)         (50)                                   
      Adenoma                                          5 (10%)      3 (6%)       6 (12%)      7 (14%)                               
      Carcinoma                                        1 (2%)       1 (2%)                                                          
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 URINARY SYSTEM                                                                                                                     
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                     1 (2%)                                                          
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)       1 (2%)                                                          
      Renal Tubule, Adenoma                                         1 (2%)                                                          
      Renal Tubule, Carcinoma                          1 (2%)                                                                       
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 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                                 1 (2%)                                
      Lymphoma Malignant                               1 (2%)                    1 (2%)       1 (2%)                                
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     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  12                                                               
NTP Experiment-Test: 88004-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 08/14/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:01:09  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       100 PPM                                   
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            43          38          29          41                                       
     Total Primary Neoplasms                           90          60          44          67                                       
   Total Animals with Benign Neoplasms                 35          24          21          27                                       
     Total Benign Neoplasms                            49          34          25          40                                       
   Total Animals with Malignant Neoplasms              26          21          14          23                                       
     Total Malignant Neoplasms                         41          26          19          27                                       
   Total Animals with Metastatic Neoplasms              9          10           4           3                                       
     Total Metastatic Neoplasm                         14          23           7           3                                       
   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  13                                                               
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