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TDMS Study 05181-03 Pathology Tables

NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02

                                                           CORE STUDY




       Facility:  Battelle Northwest

       Chemical CAS #:  0109-99-9

       Lock Date:  03/24/93

       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: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                18           22           19           19                                     
    Natural Death                                      7            3            5            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                25           25           26           26                                     
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (47)         (49)         (49)         (46)                                   
      Polyp Adenomatous                                1 (2%)                                                                       
      Sarcoma Stromal, Metastatic, Uterus                                                     1 (2%)                                
   Intestine Large, Rectum                            (48)         (50)         (50)         (47)                                   
   Intestine Large, Cecum                             (47)         (49)         (46)         (45)                                   
      Carcinoma                                                     1 (2%)                                                          
   Intestine Small, Duodenum                          (46)         (49)         (49)         (47)                                   
   Intestine Small, Ileum                             (45)         (49)         (46)         (45)                                   
   Liver                                              (50)         (49)         (50)         (50)                                   
      Osteosarcoma, Metastatic, Spleen                                           1 (2%)                                             
   Mesentery                                          (6)          (9)          (9)          (3)                                    
      Osteosarcoma, Metastatic, Spleen                                           1 (11%)                                            
   Pancreas                                           (48)         (50)         (50)         (49)                                   
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (49)         (49)         (50)         (49)                                   
      Squamous Cell Papilloma                                       1 (2%)                                                          
   Stomach, Glandular                                 (49)         (49)         (50)         (49)                                   
   Tongue                                                          (1)                       (1)                                    
      Squamous Cell Papilloma                                       1 (100%)                  1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Adenoma                                                       1 (2%)                                                          
   Adrenal Medulla                                    (50)         (50)         (49)         (50)                                   
      Pheochromocytoma Malignant                       2 (4%)                                 1 (2%)                                
      Pheochromocytoma Benign                                       1 (2%)       3 (6%)       3 (6%)                                
                                                             Page   2                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - cont                                                                                                             
   Islets, Pancreatic                                 (48)         (50)         (50)         (49)                                   
      Adenoma                                          1 (2%)       1 (2%)                    1 (2%)                                
      Carcinoma                                        1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
   Pituitary Gland                                    (49)         (49)         (50)         (50)                                   
      Pars Distalis, Adenoma                          32 (65%)     38 (78%)     38 (76%)     34 (68%)                               
      Pars Distalis, Adenoma, Multiple                 1 (2%)                                                                       
   Thyroid Gland                                      (48)         (50)         (50)         (49)                                   
      C-Cell, Adenoma                                  2 (4%)       3 (6%)       6 (12%)      4 (8%)                                
      C-Cell, Carcinoma                                2 (4%)       1 (2%)       2 (4%)       2 (4%)                                
      Follicular Cell, Adenoma                                                   1 (2%)                                             
      Follicular Cell, Carcinoma                                                              1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (48)         (48)         (46)         (49)                                   
      Adenoma                                          1 (2%)                                                                       
      Carcinoma                                        1 (2%)       1 (2%)       1 (2%)       3 (6%)                                
   Ovary                                              (50)         (50)         (50)         (50)                                   
      Granulosa-Theca Tumor Malignant                               1 (2%)                                                          
      Granulosa-Theca Tumor Benign                                                            1 (2%)                                
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Leiomyoma                                                     1 (2%)                                                          
      Polyp Stromal                                    5 (10%)      8 (16%)      8 (16%)      6 (12%)                               
      Sarcoma Stromal                                  1 (2%)       1 (2%)                    1 (2%)                                
   Vagina                                             (1)                       (1)                                                 
      Polyp                                                                      1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
   Lymph Node                                         (7)          (7)          (6)          (5)                                    
   Lymph Node, Bronchial                              (46)         (45)         (41)         (45)                                   
      Osteosarcoma, Metastatic, Spleen                                           1 (2%)                                             
   Lymph Node, Mandibular                             (45)         (47)         (48)         (44)                                   
   Lymph Node, Mesenteric                             (48)         (50)         (50)         (50)                                   
   Lymph Node, Mediastinal                            (48)         (48)         (48)         (46)                                   
      Carcinoma, Metastatic, Islets, Pancreatic                                               1 (2%)                                
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Osteosarcoma                                                               1 (2%)                                             
                                                             Page   3                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - cont                                                                                                         
   Thymus                                             (50)         (50)         (49)         (48)                                   
      Thymoma Malignant                                                                       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Adenoma                                          1 (2%)                                                                       
      Carcinoma                                        5 (10%)      5 (10%)      5 (10%)      2 (4%)                                
      Carcinoma, Multiple                                                                     1 (2%)                                
      Fibroadenoma                                    14 (28%)     14 (28%)     23 (46%)     26 (52%)                               
      Fibroadenoma, Multiple                           9 (18%)      8 (16%)      6 (12%)      5 (10%)                               
   Skin                                               (50)         (50)         (50)         (50)                                   
      Amelanotic Melanoma, Benign                                                1 (2%)                                             
      Keratoacanthoma                                  1 (2%)                    1 (2%)                                             
      Squamous Cell Papilloma                          1 (2%)       1 (2%)                                                          
      Pinna, Melanoma Benign                                                     1 (2%)                                             
      Subcutaneous Tissue, Fibroma                                               2 (4%)       1 (2%)                                
      Subcutaneous Tissue, Fibrosarcoma                             1 (2%)                                                          
      Subcutaneous Tissue, Lipoma                                                1 (2%)                                             
      Subcutaneous Tissue, Liposarcoma                 1 (2%)                                                                       
      Subcutaneous Tissue, Sarcoma                                                            1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Rib, Osteosarcoma                                1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (49)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     1 (2%)                                                                       
      Carcinoma, Metastatic, Islets, Pancreatic                                               1 (2%)                                
      Carcinoma, Metastatic, Mammary Gland                                                    1 (2%)                                
      Granulosa-Theca Tumor Malignant, Metastatic,                                                                                  
           Ovary                                                    1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   4                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Zymbal's Gland                                                               (1)                                                 
      Carcinoma                                                                  1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Granulosa-Theca Tumor Malignant, Metastatic,                                                                                  
           Ovary                                                    1 (2%)                                                          
      Lipoma                                           1 (2%)                                                                       
      Renal Tubule, Carcinoma                          1 (2%)                                                                       
   Urinary Bladder                                    (49)         (50)         (50)         (49)                                   
      Transitional Epithelium, Papilloma                            1 (2%)                                                          
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Leukemia Mononuclear                            17 (34%)     17 (34%)     18 (36%)     22 (44%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   5                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            46          47          49          48                                       
     Total Primary Neoplasms                          103         108         122         119                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 42          45          48          43                                       
     Total Benign Neoplasms                            71          79          92          82                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              27          25          23          30                                       
     Total Malignant Neoplasms                         32          29          30          37                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms                          1           1           3                                       
     Total Metastatic Neoplasm                                      2           3           4                                       
                                                                                                                                    
   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   6                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                31           39           40           34                                     
    Natural Death                                      6            4            5           10                                     
    Accidently Killed                                  1            1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                12            6            5            6                                     
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (50)         (50)         (50)                                   
   Intestine Large, Colon                             (49)         (48)         (48)         (45)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Intestine Large, Cecum                             (49)         (48)         (48)         (46)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Intestine Small, Duodenum                          (49)         (48)         (49)         (48)                                   
   Intestine Small, Jejunum                           (47)         (46)         (48)         (44)                                   
      Leiomyosarcoma                                                             1 (2%)                                             
   Intestine Small, Ileum                             (47)         (47)         (47)         (44)                                   
   Liver                                              (50)         (50)         (50)         (50)                                   
      Hepatocellular Carcinoma                         1 (2%)                                                                       
      Hepatocellular Adenoma                                        1 (2%)       1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Osteosarcoma, Metastatic, Bone                                             2 (4%)                                             
   Mesentery                                          (15)         (17)         (18)         (10)                                   
      Histiocytic Sarcoma                              1 (7%)                                                                       
      Osteosarcoma, Metastatic, Bone                                             1 (6%)                                             
   Oral Mucosa                                        (3)                                    (1)                                    
      Squamous Cell Papilloma                                                                 1 (100%)                              
   Pancreas                                           (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (50)         (49)         (49)         (50)                                   
      Squamous Cell Papilloma                          1 (2%)                                                                       
   Stomach, Glandular                                 (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Tongue                                             (1)                       (2)          (1)                                    
      Squamous Cell Papilloma                          1 (100%)                  2 (100%)     1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   7                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
      Osteosarcoma, Metastatic, Bone                                             1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Adenoma                                                                    1 (2%)                                             
      Carcinoma                                        1 (2%)                                                                       
   Adrenal Medulla                                    (48)         (50)         (50)         (49)                                   
      Pheochromocytoma Malignant                                    1 (2%)       3 (6%)       1 (2%)                                
      Pheochromocytoma Complex                                                                1 (2%)                                
      Pheochromocytoma Benign                         14 (29%)      4 (8%)      10 (20%)     11 (22%)                               
      Pheochromocytoma Benign, Multiple                4 (8%)       7 (14%)      3 (6%)       3 (6%)                                
   Islets, Pancreatic                                 (50)         (50)         (50)         (49)                                   
      Adenoma                                          4 (8%)       2 (4%)       1 (2%)       2 (4%)                                
      Carcinoma                                        1 (2%)       2 (4%)       2 (4%)       3 (6%)                                
   Pituitary Gland                                    (49)         (49)         (48)         (50)                                   
      Craniopharyngioma                                             1 (2%)                                                          
      Pars Distalis, Adenoma                          33 (67%)     34 (69%)     40 (83%)     27 (54%)                               
      Pars Distalis, Adenoma, Multiple                                                        2 (4%)                                
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      C-Cell, Adenoma                                  4 (8%)       4 (8%)                    4 (8%)                                
      C-Cell, Carcinoma                                2 (4%)       2 (4%)       3 (6%)       1 (2%)                                
      Follicular Cell, Adenoma                         2 (4%)                    1 (2%)                                             
      Follicular Cell, Carcinoma                       1 (2%)                    1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                         (2)          (2)                       (1)                                    
      Histiocytic Sarcoma                              1 (50%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
   Preputial Gland                                    (49)         (50)         (50)         (50)                                   
      Adenoma                                          2 (4%)       2 (4%)                    2 (4%)                                
      Carcinoma                                        3 (6%)       1 (2%)                    4 (8%)                                
   Prostate                                           (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Seminal Vesicle                                    (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Testes                                             (50)         (50)         (50)         (50)                                   
      Bilateral, Interstitial Cell, Adenoma           12 (24%)     14 (28%)     16 (32%)     23 (46%)                               
                                                             Page   8                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - cont                                                                                                               
      Interstitial Cell, Adenoma                      11 (22%)     17 (34%)     15 (30%)     11 (22%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node                                         (16)         (19)         (18)         (16)                                   
      Iliac, Histiocytic Sarcoma                       1 (6%)                                                                       
      Renal, Histiocytic Sarcoma                       1 (6%)                                                                       
   Lymph Node, Bronchial                              (45)         (45)         (44)         (43)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Histiocytic Sarcoma, Metastatic, Thymus                                                 1 (2%)                                
      Osteosarcoma, Metastatic, Bone                                             1 (2%)                                             
   Lymph Node, Mandibular                             (46)         (50)         (49)         (48)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node, Mesenteric                             (50)         (50)         (49)         (49)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Lymph Node, Mediastinal                            (48)         (50)         (46)         (49)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Histiocytic Sarcoma, Metastatic, Thymus                                                 1 (2%)                                
      Osteosarcoma, Metastatic, Bone                                             1 (2%)                                             
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Osteosarcoma, Metastatic, Bone                                             1 (2%)                                             
   Thymus                                             (50)         (49)         (48)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                 1 (2%)                                
      Osteosarcoma, Metastatic, Bone                                             1 (2%)                                             
      Thymoma Benign                                   1 (2%)                                                                       
      Thymoma Malignant                                                                       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Fibroadenoma                                                  1 (2%)       3 (6%)       4 (8%)                                
      Fibroadenoma, Multiple                                        1 (2%)                                                          
   Skin                                               (50)         (50)         (50)         (50)                                   
      Fibroma, Multiple                                                          1 (2%)                                             
      Keratoacanthoma                                  3 (6%)       3 (6%)       1 (2%)       2 (4%)                                
      Keratoacanthoma, Multiple                                     1 (2%)                                                          
      Schwannoma Malignant                             1 (2%)                                                                       
      Squamous Cell Carcinoma                                                                 1 (2%)                                
      Squamous Cell Papilloma                                       1 (2%)                                                          
      Trichoepithelioma                                1 (2%)                                 1 (2%)                                
      Pinna, Squamous Cell Papilloma                                1 (2%)                                                          
      Subcutaneous Tissue, Fibroma                     2 (4%)       5 (10%)      3 (6%)       2 (4%)                                
                                                             Page   9                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - cont                                                                                                         
      Subcutaneous Tissue, Fibrosarcoma                                                       1 (2%)                                
      Subcutaneous Tissue, Histiocytic Sarcoma                                                1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma, Metastatic, Skeletal                                                                                     
          Muscle                                                                 1 (2%)                                             
      Humerus, Osteosarcoma                                                      1 (2%)                                             
      Rib, Osteosarcoma                                                          1 (2%)                                             
   Skeletal Muscle                                    (1)          (1)          (1)                                                 
      Histiocytic Sarcoma                                                        1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                                                      1 (2%)                                             
      Glioma Benign                                                                           1 (2%)                                
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 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                  3 (6%)       1 (2%)                                             
      Alveolar/Bronchiolar Carcinoma                                             1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Histiocytic Sarcoma, Metastatic, Thymus                                                 1 (2%)                                
      Osteosarcoma, Metastatic, Bone                                             2 (4%)                                             
      Osteosarcoma, Metastatic, Uncertain Primary                                                                                   
          Site                                                      1 (2%)                                                          
      Pheochromocytoma Malignant, Metastatic,                                                                                       
          Adrenal Medulla                                                        1 (2%)                                             
      Squamous Cell Carcinoma                                       1 (2%)                                                          
   Pleura                                             (2)          (1)          (2)                                                 
      Histiocytic Sarcoma, Metastatic, Skeletal                                                                                     
          Muscle                                                                 1 (50%)                                            
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 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Zymbal's Gland                                     (1)          (1)                       (2)                                    
      Carcinoma                                        1 (100%)     1 (100%)                  1 (50%)                               
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                                                             Page  10                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Pelvis, Transitional Epithelium, Carcinoma                                              1 (2%)                                
      Renal Tubule, Adenoma                            1 (2%)       1 (2%)       4 (8%)       2 (4%)                                
      Renal Tubule, Adenoma, Multiple                                                         1 (2%)                                
      Renal Tubule, Carcinoma                                                                 2 (4%)                                
   Urinary Bladder                                    (50)         (50)         (49)         (50)                                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Transitional Epithelium, Carcinoma                                         1 (2%)                                             
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Histiocytic Sarcoma                              1 (2%)                    1 (2%)       2 (4%)                                
      Leukemia Mononuclear                            30 (60%)     29 (58%)     27 (54%)     32 (64%)                               
      Mesothelioma Benign                                           1 (2%)                                                          
      Mesothelioma Malignant                           2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  11                                                               
NTP Experiment-Test: 05181-03  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:50:02  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            48          49          49          50                                       
     Total Primary Neoplasms                          140         142         147         153                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 47          47          48          47                                       
     Total Benign Neoplasms                            96         104         103         100                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              37          33          32          42                                       
     Total Malignant Neoplasms                         44          38          44          53                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              1           1           4           1                                       
     Total Metastatic Neoplasm                          2           1          13           3                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms                           1                                                               
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page  12                                                               
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