https://ntp.niehs.nih.gov/go/1998

TDMS Study 05180-07 Pathology Tables

NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40
                                                      2 YEAR CHRONIC MICE
       Facility:  Battelle Northwest
       Chemical CAS #:  1303-00-0000
       Lock Date:  04/11/97
       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: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                11           11           16           11                                     
    Natural Death                                      3            3            2           10                                     
    Accidently Killed                                               2            1                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                36           34           31           29                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Gallbladder                                        (47)         (45)         (45)         (41)                                   
   Intestine Small, Duodenum                          (48)         (47)         (50)         (46)                                   
   Intestine Small, Jejunum                           (48)         (47)         (49)         (43)                                   
      Carcinoma                                                                               1 (2%)                                
      Polyp Adenomatous                                             1 (2%)                                                          
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma                         8 (16%)      9 (18%)      4 (8%)       5 (10%)                               
      Hepatocellular Carcinoma, Multiple               4 (8%)       2 (4%)                    3 (6%)                                
      Hepatocellular Adenoma                           9 (18%)      9 (18%)     12 (24%)      8 (16%)                               
      Hepatocellular Adenoma, Multiple                 2 (4%)       1 (2%)                    2 (4%)                                
      Hepatocholangiocarcinoma                                                                2 (4%)                                
      Hepatocholangiocarcinoma, Multiple                                         1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Mesentery                                          (8)          (9)          (16)         (13)                                   
      Hemangiosarcoma                                                            1 (6%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver                                1 (6%)       1 (8%)                                
      Sarcoma, Metastatic, Skin                        2 (25%)                                1 (8%)                                
      Teratoma Malignant, Metastatic, Ovary                                      1 (6%)                                             
   Pancreas                                           (50)         (50)         (50)         (49)                                   
      Sarcoma, Metastatic, Skin                        2 (4%)                                                                       
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (49)         (50)         (50)         (49)                                   
      Squamous Cell Papilloma                                                                 3 (6%)                                
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                               1 (2%)                                                          
      Hepatocholangiocarcinoma, Metastatic, Liver                                             1 (2%)                                
____________________________________________________________________________________________________________________________________
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Medulla                                    (50)         (49)         (50)         (49)                                   
      Pheochromocytoma Benign                                                    1 (2%)       1 (2%)                                
   Islets, Pancreatic                                 (50)         (50)         (50)         (48)                                   
      Adenoma                                          1 (2%)                                                                       
   Pituitary Gland                                    (46)         (48)         (50)         (47)                                   
      Pars Distalis, Adenoma                           3 (7%)       7 (15%)      5 (10%)      7 (15%)                               
      Pars Distalis, Carcinoma                                                   1 (2%)                                             
      Pars Intermedia, Adenoma                                                   2 (4%)                                             
      Pars Intermedia, Carcinoma                                                 2 (4%)                                             
   Thyroid Gland                                      (50)         (50)         (50)         (49)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                                             1 (2%)                                
      C-Cell, Carcinoma                                1 (2%)                                                                       
      Follicular Cell, Adenoma                         1 (2%)                                 2 (4%)                                
      Follicular Cell, Carcinoma                                                              2 (4%)                                
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Ovary                                              (49)         (50)         (50)         (46)                                   
      Cystadenoma                                      2 (4%)       1 (2%)       1 (2%)       3 (7%)                                
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
      Teratoma Malignant                                                         1 (2%)                                             
      Thecoma Benign                                                             1 (2%)                                             
      Tubulostromal Adenoma                            1 (2%)                                                                       
   Uterus                                             (49)         (50)         (50)         (50)                                   
      Carcinoma                                        1 (2%)                                                                       
      Hemangioma                                                                 1 (2%)                                             
      Leiomyoma                                                     1 (2%)                    1 (2%)                                
      Leiomyosarcoma                                   1 (2%)                                                                       
      Polyp Stromal                                    1 (2%)       2 (4%)       2 (4%)       2 (4%)                                
      Sarcoma Stromal                                                            1 (2%)                                             
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       1 (2%)                                                          
   Lymph Node                                         (4)          (8)          (5)          (6)                                    
      Sarcoma, Metastatic, Skin                        1 (25%)                                1 (17%)                               
      Teratoma Malignant, Metastatic, Ovary                                      1 (20%)                                            
      Pancreatic, Hepatocholangiocarcinoma,                                                                                         
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - cont                                                                                                         
          Metastatic, Liver                                                                   1 (17%)                               
   Lymph Node, Bronchial                              (39)         (43)         (42)         (42)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                                1 (2%)                                             
      Histiocytic Sarcoma                              1 (3%)                                                                       
   Lymph Node, Mandibular                             (35)         (37)         (43)         (43)                                   
   Lymph Node, Mesenteric                             (49)         (49)         (50)         (47)                                   
      Hemangiosarcoma                                                            1 (2%)                                             
      Hepatocholangiocarcinoma, Metastatic, Liver                                1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sarcoma, Metastatic, Skin                        1 (2%)                                                                       
   Lymph Node, Mediastinal                            (40)         (43)         (49)         (45)                                   
      Carcinoma, Metastatic, Harderian Gland           1 (3%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver                                1 (2%)       2 (4%)                                
      Sarcoma, Metastatic, Skin                        1 (3%)                                                                       
   Spleen                                             (50)         (50)         (50)         (49)                                   
      Hemangiosarcoma                                               2 (4%)       2 (4%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Thymus                                             (43)         (47)         (43)         (44)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                                             1 (2%)                                
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Mammary Gland                                      (50)         (50)         (50)         (49)                                   
      Carcinoma                                        1 (2%)       1 (2%)       1 (2%)       2 (4%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Subcutaneous Tissue, Carcinoma                                             1 (2%)                                             
      Subcutaneous Tissue, Hemangioma                                            1 (2%)                                             
      Subcutaneous Tissue, Sarcoma                     4 (8%)       4 (8%)       2 (4%)       4 (8%)                                
      Subcutaneous Tissue, Schwannoma Benign                                     1 (2%)                                             
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Bone                                               (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)                                                                       
   Skeletal Muscle                                    (1)          (2)          (1)          (1)                                    
      Carcinoma, Metastatic, Harderian Gland           1 (100%)                                                                     
      Hemangiosarcoma                                                            1 (100%)                                           
      Hepatocholangiocarcinoma, Metastatic, Liver                                             1 (100%)                              
____________________________________________________________________________________________________________________________________
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   Brain                                              (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Pituitary Gland                                     3 (6%)                                             
      Oligodendroglioma Benign                                                                1 (2%)                                
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Larynx                                             (50)         (50)         (50)         (50)                                   
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     6 (12%)      4 (8%)       1 (2%)       3 (6%)                                
      Alveolar/Bronchiolar Carcinoma                   1 (2%)                    3 (6%)       2 (4%)                                
      Alveolar/Bronchiolar Carcinoma, Multiple                                                1 (2%)                                
      Carcinoma, Metastatic, Harderian Gland           2 (4%)                                                                       
      Hepatocellular Carcinoma, Metastatic, Liver      4 (8%)       3 (6%)       2 (4%)       3 (6%)                                
      Hepatocellular Carcinoma, Metastatic, Lung                                              1 (2%)                                
      Hepatocholangiocarcinoma, Metastatic, Liver                                1 (2%)       2 (4%)                                
      Sarcoma, Metastatic, Skin                                                               1 (2%)                                
      Teratoma Malignant, Metastatic, Ovary                                      1 (2%)                                             
      Mediastinum, Carcinoma, Metastatic,                                                                                           
          Harderian Gland                              1 (2%)                                                                       
      Mediastinum, Hemangioma                                                    1 (2%)                                             
      Mediastinum, Hepatocholangiocarcinoma,                                                                                        
          Metastatic, Liver                                                      1 (2%)       1 (2%)                                
      Mediastinum, Sarcoma, Metastatic, Skin           1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Harderian Gland                                    (5)          (4)          (3)          (2)                                    
      Adenoma                                          2 (40%)      3 (75%)      2 (67%)      2 (100%)                              
      Carcinoma                                        3 (60%)      1 (25%)      1 (33%)                                            
____________________________________________________________________________________________________________________________________
 URINARY SYSTEM                                                                                                                     
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Hepatocholangiocarcinoma, Metastatic, Liver                                1 (2%)       1 (2%)                                
      Teratoma Malignant, Metastatic, Ovary                                      1 (2%)                                             
   Urinary Bladder                                    (48)         (48)         (50)         (48)                                   
      Hemangioma                                                    1 (2%)                                                          
____________________________________________________________________________________________________________________________________
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   5                                                               
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
 SYSTEMIC LESIONS - cont                                                                                                            
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Lymphoma Malignant                               3 (6%)       8 (16%)     11 (22%)     10 (20%)                               
____________________________________________________________________________________________________________________________________
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            36          36          40          39                                       
     Total Primary Neoplasms                           58          59          65          67                                       
   Total Animals with Benign Neoplasms                 22          24          26          22                                       
     Total Benign Neoplasms                            28          30          31          35                                       
   Total Animals with Malignant Neoplasms              26          23          26          26                                       
     Total Malignant Neoplasms                         30          29          34          32                                       
   Total Animals with Metastatic Neoplasms              9           3           6           7                                       
     Total Metastatic Neoplasm                         18           3          16          19                                       
   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                                                                              
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 7            8           10            7                                     
    Natural Death                                      8            4            6            9                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                35           38           34           34                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
 ALIMENTARY SYSTEM                                                                                                                  
   Intestine Large, Cecum                             (44)         (49)         (44)         (42)                                   
      Polyp Adenomatous                                             1 (2%)                                                          
   Intestine Small, Duodenum                          (42)         (46)         (45)         (43)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Intestine Small, Jejunum                           (44)         (48)         (45)         (43)                                   
      Carcinoma                                        2 (5%)       2 (4%)                    1 (2%)                                
      Hemangiosarcoma                                                                         1 (2%)                                
   Intestine Small, Ileum                             (44)         (47)         (45)         (42)                                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                  1 (2%)       2 (4%)       3 (6%)       1 (2%)                                
      Hepatocellular Carcinoma                        10 (20%)      7 (14%)     10 (20%)     14 (28%)                               
      Hepatocellular Carcinoma, Multiple               3 (6%)       2 (4%)       2 (4%)       3 (6%)                                
      Hepatocellular Adenoma                          11 (22%)     13 (26%)     12 (24%)     15 (30%)                               
      Hepatocellular Adenoma, Multiple                 5 (10%)      5 (10%)      7 (14%)      2 (4%)                                
      Hepatocholangiocarcinoma                                      2 (4%)                                                          
      Histiocytic Sarcoma                              2 (4%)                                 1 (2%)                                
   Mesentery                                          (4)          (5)          (4)          (6)                                    
      Hemangioma                                       1 (25%)                                                                      
      Hemangiosarcoma                                  2 (50%)                                                                      
      Sarcoma                                                                    1 (25%)                                            
   Pancreas                                           (50)         (50)         (49)         (47)                                   
      Sarcoma, Metastatic, Mesentery                                             1 (2%)                                             
   Stomach, Forestomach                               (50)         (50)         (49)         (49)                                   
      Squamous Cell Papilloma                          1 (2%)                                 1 (2%)                                
   Tooth                                              (1)          (3)          (1)          (1)                                    
      Odontoma                                                      1 (33%)                                                         
____________________________________________________________________________________________________________________________________
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
 CARDIOVASCULAR SYSTEM                                                                                                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Hemangiosarcoma                                                            1 (2%)                                             
____________________________________________________________________________________________________________________________________
 ENDOCRINE SYSTEM                                                                                                                   
   Adrenal Cortex                                     (50)         (50)         (50)         (48)                                   
      Adenoma                                                                                 1 (2%)                                
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Capsule, Adenoma                                                           1 (2%)                                             
   Adrenal Medulla                                    (50)         (50)         (50)         (47)                                   
      Pheochromocytoma Benign                          1 (2%)                                                                       
   Islets, Pancreatic                                 (50)         (48)         (49)         (47)                                   
      Adenoma                                                                    3 (6%)                                             
   Thyroid Gland                                      (50)         (50)         (50)         (48)                                   
      Follicular Cell, Adenoma                         1 (2%)       1 (2%)                                                          
      Follicular Cell, Carcinoma                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 GENERAL BODY SYSTEM                                                                                                                
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
 GENITAL SYSTEM                                                                                                                     
   Epididymis                                         (50)         (50)         (50)         (49)                                   
   Prostate                                           (50)         (49)         (49)         (49)                                   
   Seminal Vesicle                                    (50)         (50)         (48)         (43)                                   
      Hemangioma                                       1 (2%)                                                                       
   Testes                                             (50)         (50)         (50)         (50)                                   
      Hemangioma                                                    1 (2%)                                                          
      Interstitial Cell, Adenoma                                                 2 (4%)                                             
____________________________________________________________________________________________________________________________________
 HEMATOPOIETIC SYSTEM                                                                                                               
   Bone Marrow                                        (49)         (50)         (50)         (48)                                   
      Hemangiosarcoma                                                            2 (4%)       1 (2%)                                
   Lymph Node                                         (2)                       (2)          (1)                                    
      Pancreatic, Histiocytic Sarcoma                  1 (50%)                                                                      
      Renal, Hemangiosarcoma                                                                  1 (100%)                              
   Lymph Node, Bronchial                              (38)         (37)         (40)         (41)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
   Lymph Node, Mandibular                             (37)         (40)         (28)         (32)                                   
      Histiocytic Sarcoma                              1 (3%)                                                                       
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - cont                                                                                                         
   Lymph Node, Mesenteric                             (48)         (49)         (50)         (46)                                   
      Histiocytic Sarcoma                              1 (2%)                                 1 (2%)                                
   Lymph Node, Mediastinal                            (38)         (36)         (38)         (33)                                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (3%)                                                                       
      Histiocytic Sarcoma                                                                     1 (3%)                                
   Spleen                                             (50)         (50)         (49)         (47)                                   
      Hemangiosarcoma                                  2 (4%)                    2 (4%)       1 (2%)                                
   Thymus                                             (38)         (36)         (38)         (35)                                   
____________________________________________________________________________________________________________________________________
 INTEGUMENTARY SYSTEM                                                                                                               
   Skin                                               (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sebaceous Gland, Adenoma                         1 (2%)                                                                       
      Subcutaneous Tissue, Hemangiosarcoma                                       1 (2%)                                             
      Subcutaneous Tissue, Lipoma                      1 (2%)       1 (2%)                    1 (2%)                                
____________________________________________________________________________________________________________________________________
 MUSCULOSKELETAL SYSTEM                                                                                                             
   Bone                                               (49)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
 NERVOUS SYSTEM                                                                                                                     
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
 RESPIRATORY SYSTEM                                                                                                                 
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                    12 (24%)      8 (16%)     10 (20%)      6 (12%)                               
      Alveolar/Bronchiolar Adenoma, Multiple           1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Alveolar/Bronchiolar Carcinoma                   3 (6%)       4 (8%)       6 (12%)      6 (12%)                               
      Alveolar/Bronchiolar Carcinoma, Multiple                      2 (4%)                                                          
      Carcinoma, Metastatic, Harderian Gland           1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
      Hemangiosarcoma                                                            1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic, Liver      3 (6%)       1 (2%)       2 (4%)       2 (4%)                                
      Histiocytic Sarcoma                              1 (2%)                                 1 (2%)                                
      Mediastinum, Alveolar/Bronchiolar Carcinoma,                                                                                  
           Metastatic, Lung                                                      1 (2%)                                             
      Mediastinum, Hepatocellular Carcinoma,                                                                                        
          Metastatic, Liver                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
 SPECIAL SENSES SYSTEM                                                                                                              
   Ear                                                                          (1)                                                 
      Hemangiosarcoma                                                            1 (100%)                                           
   Harderian Gland                                    (47)         (48)         (49)         (48)                                   
      Adenoma                                          3 (6%)       6 (13%)      8 (16%)      8 (17%)                               
      Adenoma, Multiple                                1 (2%)                                                                       
      Carcinoma                                        1 (2%)       1 (2%)       3 (6%)       4 (8%)                                
____________________________________________________________________________________________________________________________________
 URINARY SYSTEM                                                                                                                     
   Kidney                                             (50)         (50)         (49)         (48)                                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                                             1 (2%)                                             
      Renal Tubule, Adenoma                                                                   1 (2%)                                
   Urinary Bladder                                    (49)         (50)         (46)         (46)                                   
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 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              3 (6%)                                 1 (2%)                                
      Lymphoma Malignant                               1 (2%)       1 (2%)       2 (4%)       1 (2%)                                
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     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  11                                                               
NTP Experiment-Test: 05180-07  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          GALLIUM ARSENIDE                                     Date: 03/09/99  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 14:24:40  
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         B6C3F1 MICE MALE                          CONTROL      0.1          0.5          1.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
TUMOR SUMMARY                                                                                                                       
   Total Animals with Primary Neoplasms (b)            40          37          45          41                                       
     Total Primary Neoplasms                           69          62          79          71                                       
   Total Animals with Benign Neoplasms                 30          28          33          28                                       
     Total Benign Neoplasms                            40          39          44          36                                       
   Total Animals with Malignant Neoplasms              23          20          26          29                                       
     Total Malignant Neoplasms                         29          23          35          35                                       
   Total Animals with Metastatic Neoplasms              4           2           5           3                                       
     Total Metastatic Neoplasm                          9           2           6           3                                       
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
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                             ----------              END OF REPORT             ----------                                           
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