National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/17645

TDMS Study 88004-05 Pathology Tables

NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59

                                                         FINAL #1 RATS




       Facility:  Battelle Northwest

       Chemical CAS #:  1321-74-0

       Lock Date:  04/16/02

       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: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                10           16           14           26                                     
    Natural Death                                      7            3            3            2                                     
    Accidently Killed                                               1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                33           30           33           22                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma                                                   1 (2%)                                             
      Hepatocellular Adenoma                                        2 (4%)                                                          
      Hepatocellular Adenoma, Multiple                                           2 (4%)                                             
      Histiocytic Sarcoma, Metastatic, Spleen          1 (2%)                                                                       
   Mesentery                                          (15)         (20)         (17)         (6)                                    
      Carcinoma, Metastatic, Liver                                               1 (6%)                                             
   Pancreas                                           (50)         (49)         (50)         (50)                                   
   Tongue                                             (1)          (1)          (3)          (3)                                    
      Squamous Cell Papilloma                                       1 (100%)                  1 (33%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Carcinoma                                                                               1 (2%)                                
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Pheochromocytoma Malignant                                                 1 (2%)       1 (2%)                                
      Pheochromocytoma Benign                          2 (4%)       2 (4%)       3 (6%)       1 (2%)                                
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   2                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - cont                                                                                                             
      Bilateral, Pheochromocytoma Benign                                                      1 (2%)                                
   Islets, Pancreatic                                 (50)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)                    1 (2%)       1 (2%)                                
      Carcinoma                                                                               1 (2%)                                
   Pituitary Gland                                    (50)         (50)         (50)         (50)                                   
      Pars Distalis, Adenoma                          37 (74%)     34 (68%)     39 (78%)     28 (56%)                               
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
      C-Cell, Adenoma                                               5 (10%)      1 (2%)       4 (8%)                                
      C-Cell, Carcinoma                                1 (2%)       1 (2%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (50)         (50)         (50)                                   
      Carcinoma                                                                  1 (2%)                                             
   Ovary                                              (50)         (50)         (50)         (50)                                   
      Granulosa Cell Tumor Benign                                   1 (2%)                                                          
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)                                                                       
      Carcinoma                                                                               1 (2%)                                
      Polyp Stromal                                    9 (18%)      6 (12%)      8 (16%)      6 (12%)                               
      Sarcoma Stromal                                               1 (2%)                                                          
      Schwannoma Malignant                                          1 (2%)                                                          
      Bilateral, Polyp Stromal                                                                1 (2%)                                
      Cervix, Sarcoma Stromal                                       1 (2%)                                                          
   Vagina                                                          (2)                       (3)                                    
      Sarcoma                                                       1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (6)          (10)         (9)          (8)                                    
      Deep Cervical, Carcinoma, Metastatic,                                                                                         
          Zymbal's Gland                               1 (17%)                                                                      
      Pancreatic, Carcinoma, Metastatic, Mammary                                                                                    
          Gland                                                     1 (10%)                                                         
      Pancreatic, Histiocytic Sarcoma, Metastatic,                                                                                  
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   3                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - cont                                                                                                         
           Spleen                                      1 (17%)                                                                      
   Lymph Node, Bronchial                              (8)          (9)          (5)          (14)                                   
   Lymph Node, Mandibular                             (3)          (1)          (5)          (3)                                    
   Lymph Node, Mesenteric                             (50)         (50)         (50)         (50)                                   
   Lymph Node, Mediastinal                            (32)         (37)         (44)         (34)                                   
      Carcinoma, Metastatic, Mammary Gland                          1 (3%)                                                          
      Carcinoma, Metastatic, Zymbal's Gland            1 (3%)                                                                       
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Thymus                                             (45)         (41)         (46)         (39)                                   
      Thymoma Malignant                                                          1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Adenoma                                                       1 (2%)                                                          
      Carcinoma                                        3 (6%)       4 (8%)       3 (6%)                                             
      Carcinoma, Multiple                                           1 (2%)       1 (2%)                                             
      Fibroadenoma                                    14 (28%)     14 (28%)     13 (26%)      9 (18%)                               
      Fibroadenoma, Multiple                           6 (12%)      8 (16%)      6 (12%)      5 (10%)                               
   Skin                                               (50)         (50)         (50)         (50)                                   
      Basal Cell Carcinoma                                          1 (2%)                                                          
      Subcutaneous Tissue, Histiocytic Sarcoma         1 (2%)                                                                       
      Subcutaneous Tissue, Lipoma                                                1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Femur, Osteosarcoma                                                                     1 (2%)                                
      Vertebra, Osteosarcoma                                        1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   4                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (49)         (50)                                   
      Carcinoma, Metastatic, Thyroid Gland             1 (2%)                                                                       
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                                            2 (4%)                                
      Carcinoma, Metastatic, Liver                                               1 (2%)                                             
      Carcinoma, Metastatic, Mammary Gland                          1 (2%)                                                          
      Carcinoma, Metastatic, Thyroid Gland                                       1 (2%)                                             
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
      Osteosarcoma, Metastatic, Bone                                1 (2%)                    1 (2%)                                
   Nose                                               (50)         (50)         (49)         (49)                                   
      Respiratory Epithelium, Adenoma                                                         1 (2%)                                
   Pleura                                             (50)         (50)         (50)         (49)                                   
      Osteosarcoma, Metastatic, Bone                                                          1 (2%)                                
   Trachea                                            (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (50)         (48)         (49)         (49)                                   
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Adenoma                                                                                 1 (2%)                                
      Carcinoma, Metastatic, Zymbal's Gland            1 (2%)                                                                       
   Zymbal's Gland                                     (1)                                    (2)                                    
      Carcinoma                                        1 (100%)                               2 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (49)         (50)                                   
      Osteosarcoma, Metastatic, Bone                                                          1 (2%)                                
   Urinary Bladder                                    (50)         (50)         (49)         (49)                                   
      Transitional Epithelium, Carcinoma                                         1 (2%)                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   5                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
                                                                                                                                    
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              2 (4%)                                                                       
      Leukemia Mononuclear                            10 (20%)     18 (36%)     22 (44%)     22 (44%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   6                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            46          46          49          47                                       
     Total Primary Neoplasms                           87         104         107          90                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 43          42          45          36                                       
     Total Benign Neoplasms                            70          74          74          61                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              17          27          28          27                                       
     Total Malignant Neoplasms                         17          30          33          29                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              3           2           2           1                                       
     Total Metastatic Neoplasm                         13           5           3           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: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                15            9           12           13                                     
    Natural Death                                      4            6            6            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                31           35           31           32                                     
    Natural Death                                                                1                                                  
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (48)         (48)         (48)         (49)                                   
      Adenoma                                                       1 (2%)                                                          
      Polyp Adenomatous                                                          1 (2%)                                             
   Intestine Large, Cecum                             (47)         (48)         (46)         (49)                                   
      Polyp Adenomatous                                             1 (2%)                                                          
   Intestine Small, Jejunum                           (46)         (47)         (47)         (46)                                   
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
   Intestine Small, Ileum                             (46)         (47)         (45)         (46)                                   
      Fibrosarcoma                                                                            1 (2%)                                
   Liver                                              (50)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Islets, Pancreatic                                               1 (2%)                                
      Fibrous Histiocytoma, Metastatic, Skin                        1 (2%)                    1 (2%)                                
      Osteosarcoma, Metastatic, Bone                   1 (2%)                                                                       
      Osteosarcoma, Metastatic, Uncertain Primary                                                                                   
          Site                                                      1 (2%)                                                          
      Pheochromocytoma Malignant, Metastatic,                                                                                       
          Adrenal Medulla                                                        1 (2%)                                             
   Mesentery                                          (12)         (13)         (18)         (11)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (9%)                                
      Histiocytic Sarcoma                              1 (8%)                                                                       
      Leiomyosarcoma, Metastatic, Stomach,                                                                                          
          Glandular                                    1 (8%)                                                                       
   Oral Mucosa                                        (1)                       (1)          (4)                                    
      Pharyngeal, Squamous Cell Papilloma                                                     1 (25%)                               
   Pancreas                                           (50)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Fibrous Histiocytoma, Metastatic, Skin                        1 (2%)                                                          
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   8                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - cont                                                                                                            
      Leiomyosarcoma, Metastatic, Stomach,                                                                                          
          Glandular                                    1 (2%)                                                                       
      Acinus, Adenoma                                                                         1 (2%)                                
   Stomach, Forestomach                               (50)         (48)         (50)         (50)                                   
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
   Stomach, Glandular                                 (50)         (48)         (50)         (49)                                   
      Leiomyosarcoma                                   1 (2%)                                                                       
   Tongue                                             (1)          (1)                                                              
      Squamous Cell Papilloma                          1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (50)         (50)                                   
   Heart                                              (50)         (50)         (50)         (50)                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Osteosarcoma, Metastatic, Bone                                1 (2%)                                                          
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Osteosarcoma, Metastatic, Bone                   1 (2%)                                                                       
      Pheochromocytoma Malignant                       1 (2%)       2 (4%)       2 (4%)       1 (2%)                                
      Pheochromocytoma Benign                         12 (24%)      3 (6%)       8 (16%)      7 (14%)                               
      Bilateral, Pheochromocytoma Benign                            1 (2%)       1 (2%)                                             
   Islets, Pancreatic                                 (50)         (48)         (50)         (50)                                   
      Adenoma                                          5 (10%)      8 (17%)      2 (4%)       9 (18%)                               
      Carcinoma                                        1 (2%)                    1 (2%)       1 (2%)                                
   Pituitary Gland                                    (50)         (50)         (50)         (49)                                   
      Pars Distalis, Adenoma                          36 (72%)     30 (60%)     31 (62%)     29 (59%)                               
      Pars Distalis, Ganglioneuroma                                                           1 (2%)                                
      Pars Intermedia, Adenoma                                      2 (4%)                                                          
   Thyroid Gland                                      (50)         (50)         (50)         (49)                                   
      C-Cell, Adenoma                                  2 (4%)       5 (10%)      2 (4%)       2 (4%)                                
      C-Cell, Carcinoma                                1 (2%)                                 1 (2%)                                
      Follicular Cell, Adenoma                         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   9                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                         (40)         (49)         (50)         (49)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
   Preputial Gland                                    (48)         (50)         (50)         (49)                                   
      Adenoma                                                       1 (2%)                    1 (2%)                                
      Carcinoma                                                     1 (2%)                    1 (2%)                                
   Prostate                                           (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
   Seminal Vesicle                                    (50)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
   Testes                                             (50)         (50)         (50)         (50)                                   
      Bilateral, Interstitial Cell, Adenoma           20 (40%)     32 (64%)     27 (54%)     32 (64%)                               
      Interstitial Cell, Adenoma                      18 (36%)     13 (26%)     16 (32%)     10 (20%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Fibrous Histiocytoma, Metastatic, Skin                        1 (2%)                                                          
   Lymph Node                                         (11)         (5)          (11)         (6)                                    
   Lymph Node, Bronchial                              (7)          (6)          (12)         (5)                                    
   Lymph Node, Mesenteric                             (49)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Sarcoma                                          1 (2%)                                                                       
   Lymph Node, Mediastinal                            (19)         (23)         (25)         (38)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (3%)                                
   Spleen                                             (50)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
      Fibrous Histiocytoma, Metastatic, Skin                        1 (2%)                    1 (2%)                                
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
   Thymus                                             (48)         (44)         (46)         (42)                                   
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                                                             Page  10                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (35)         (43)         (47)         (48)                                   
      Adenoma, Multiple                                             1 (2%)                                                          
      Carcinoma                                        1 (3%)                    1 (2%)                                             
      Fibroadenoma                                     1 (3%)                    5 (11%)      1 (2%)                                
      Fibroadenoma, Multiple                                                                  1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Basal Cell Adenoma                                                         1 (2%)       3 (6%)                                
      Squamous Cell Papilloma                          1 (2%)                                                                       
      Trichoepithelioma                                1 (2%)                                                                       
      Subcutaneous Tissue, Fibroma                     5 (10%)      7 (14%)      4 (8%)       3 (6%)                                
      Subcutaneous Tissue, Fibrous Histiocytoma                     1 (2%)                    1 (2%)                                
      Subcutaneous Tissue, Fibrous Histiocytoma,                                                                                    
           Multiple                                    1 (2%)                                                                       
      Subcutaneous Tissue, Lipoma                      1 (2%)       1 (2%)       1 (2%)                                             
      Subcutaneous Tissue, Myxoma                                                             1 (2%)                                
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 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Femur, Osteosarcoma                                           1 (2%)                                                          
      Pelvis, Femur, Osteosarcoma                      1 (2%)                                                                       
   Skeletal Muscle                                    (2)          (6)          (1)          (4)                                    
      Carcinoma, Metastatic, Kidney                                                           1 (25%)                               
      Fibrous Histiocytoma, Metastatic, Skin                        1 (17%)                                                         
      Osteosarcoma                                                  1 (17%)                                                         
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 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                                      2 (4%)                                             
      Oligodendroglioma Malignant                                   1 (2%)       1 (2%)                                             
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 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                  1 (2%)                                                          
      Alveolar/Bronchiolar Adenoma, Multiple                                                  1 (2%)                                
      Alveolar/Bronchiolar Carcinoma                   1 (2%)                    1 (2%)                                             
      Carcinoma, Metastatic, Kidney                                                           1 (2%)                                
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  11                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - cont                                                                                                           
      Fibrous Histiocytoma, Metastatic, Skin           1 (2%)       1 (2%)                    1 (2%)                                
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
      Osteosarcoma, Metastatic, Bone                   1 (2%)       1 (2%)                                                          
      Osteosarcoma, Metastatic, Uncertain Primary                                                                                   
          Site                                                      1 (2%)                                                          
      Squamous Cell Carcinoma                                                    1 (2%)                                             
   Nose                                               (50)         (48)         (50)         (49)                                   
   Pleura                                             (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
      Leiomyosarcoma, Metastatic, Stomach,                                                                                          
          Glandular                                    1 (2%)                                                                       
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 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Zymbal's Gland                                     (1)                       (3)                                                 
      Carcinoma                                                                  2 (67%)                                            
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 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (49)         (50)         (49)                                   
      Histiocytic Sarcoma, Metastatic, Mesentery       1 (2%)                                                                       
      Liposarcoma                                      1 (2%)                                                                       
      Pelvis, Transitional Epithelium, Carcinoma       1 (2%)       1 (2%)                                                          
      Renal Tubule, Carcinoma                                                                 2 (4%)                                
   Urinary Bladder                                    (50)         (49)         (50)         (49)                                   
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 SYSTEMIC LESIONS                                                                                                                   
                                                                                                                                    
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Leukemia Mononuclear                            22 (44%)     13 (26%)     14 (28%)     10 (20%)                               
      Mesothelioma Malignant                           2 (4%)       2 (4%)       1 (2%)       2 (4%)                                
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     *   Number of animals with any tissue examined microscopically                                                                 
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  12                                                               
                                                                                                                                   
NTP Experiment-Test: 88004-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                           DIVINYLBENZENE                                      Date: 12/17/03  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:42:59  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      100 PPM      200 PPM      400 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            50          49          49          49                                       
     Total Primary Neoplasms                          140         130         125         123                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 49          49          48          48                                       
     Total Benign Neoplasms                           104         107          99         103                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              29          20          24          18                                       
     Total Malignant Neoplasms                         36          23          26          20                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              5           3           1           3                                       
     Total Metastatic Neoplasm                         19          10           1          15                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms                           1                                                               
   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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                             ----------              END OF REPORT             ----------                                           
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NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.