Cnapter 4 



SPONTANEOUS NEOPLASMS IN MICE 



By Arthur M. Cloudman, Roscoe B. Jackson Memorial Laboratory . 



Introduction, i68. Definition and characteristics of tumors, 169. Classification of 

 tumors, 171. Histological classification of mouse tumors, 172. Tumors of the 

 mammary region, 174. Classification of tumors in or near the mammary glands, 175. 

 Adenomas of the mammary glands, 176. Adenocarcinomas of the mammary glands, 

 182. Carcinoma simplex of the mammary glands, 190. Carcinosarcoma of the 

 mammary glands, 192. Fibrosarcoma of the mammary gland stroma, 192. Tumors 

 in or near the mammary line and its branches but not originating from the mammary 

 gland proper, 193. Tumors of the skin, subcutaneous and body wall tissues, 195. 

 Tumors of the epidermis, 195. Tumors of the dermis, subcutaneous and body wall 

 tissues, 199. Tumors of the lung, 208. Tmnors of the blood forming and blood 

 destroying tissues, 212. Lymphocyte tumors, 215. Myeloid cell tumors, 216. 

 Monocyte tumors, 217. Tumors of the digestive system and associated glands, 219. 

 Digestive tube and submaxillary gland tumors, 219. Hepatic and gall bladder 

 tumors, 219. Pancreatic tumors, 221. Tumors of the uro -genital system, 221. 

 Kidney and urinary bladder tumors, 221. Ovarian tumors, 222. Uterine tumors, 

 225. Tumors of the testes, 227. Tumors of the central nervous system, 228. Other 

 rare sites of tumors, 229. BibUography, 230. 



Introduction 



In our laboratory there have been over 20,000 mice that have developed 

 spontaneous tumors. Many of these mice have developed multiple tumors 

 involving different regions of the body. All of these cases have been care- 

 fully recorded and permanent preparations have been made of the vast 

 majority of these tissues. Some have been studied as frozen sections. 



As in the case of human neoplasms, practically all body regions have 

 given rise to spontaneous new grov^ths. Also, as with tumors in humans, the 

 malignant nature of mouse neoplasms has been definitely established (23, 

 71). This has been a natural result of the enormous amount of research 

 involving the investigation of all phases of mouse tumors since their value 

 for this purpose was pointed out over forty years ago (42). 



In this section spontaneous tumors will be treated as fully as the space 

 permits. Most of the tumors described have occurred in the Roscoe B. 

 Jackson Memorial Laboratory mice. 



168 



