The Corwarative Pathology O F Carcinoma O F the Pancreas, with Report O F Two Cases in Mice

From the scanty evidence furnished by case reports, it is apparent that carcinoma of the pancreas is relatively rare in other animals as compared to its occurrence in man. According to the review of the literature on carcinoma of the pancreas in man by Kiefer (l), in 174,803 autopsies 1420 primary carcinomas of the pancreas were found, about 0.8 per cent, and among 50,494 admissions to Johns Hopkins Hospital there were recognized 58 cases of pancreatic cancer. From these and other reports it appears that the pancreas is the site of about one per cent of all the primary carcinomas. This is in marked contrast with our experience in finding but two primary carcinomas of the pancreas in 125,000 mice examined after natural death, among approximately 20,000 other spontaneous tumors. The statement has been made that new growths of the pancreas are common in old dogs (as by Mayo Robson and Cammidge, quoted by Kiefer), but we have been unable to locate specific evidence of a sufficient number of cases to support this generalization. Schlegel (2) says : “Malignant epithelial neoplasms of the pancreas have so fa r been observed only a few times in dogs and cats.” He reported a case of pancreas adenoma in a six-year-old male St. Bernard. One might expect dogs to show this condition more frequently in view of the fact that nodular hyperplasia is often found in the canine pancreas. Baumgartner (3) examined the pancreas in 121 dogs, mostly old, and found nodular hyperplasia in 88; of 101 dogs over seven years old, 86 (85.1 per cent) showed hyperplasia, but in none was there any evidence of malignancy. Cohrs (4) has also noted the frequency of such hyperplasias, also without observing malignant growths. From his extensive experience Kitt ( 5 ) reports but one case of scirrhous carcinoma of the pancreas in a dog, and refers to one reported by Nocard. Of particular interest is the case reported by Bru (6) of what seemed to be a primary carcinoma arising in the islands of Langerhans in a dog, with metastases in the lung, heart, liver, and lymph n0des.l Borrel (7) has reported as cancer of the pancreas, a tumor associated with a mesenteric