Spontaneous Tumors and Pathologic Lesions in SWR/J Mice23

Abstract

A colony of SWR/J mice was studied for a life history profile. Of 671 mice, 3–30 months old, examined histologically, 414 (61.7%) had 1 or more tumors. The incidence of lung tumors was 36%. Mammary tumors were present in 29.7% of the females. Among the rare tumors observed were 3 epidermoid carcinomas of the forestomach, 1 adenocarcinoma each of the glandular stomach and duodenum, and 4 pheochromocytomas of the adrenal medulla. Non-neoplastic proliferation occurred occasionally in the biliary tract and frequently in the male adrenal medulla.