title: Spontaneous gastric carcinomas in sooty mangabeys (Cercocebus atys).
abstract: Sooty mangabeys (Cercocebus atys) are native to West Africa and are a natural host of SIV, which is implicated in the origin of HIV2. They have been used in studies of AIDS pathogenesis, leprosy, immune responses, reproductive biology, and behavior. Spontaneous tumors have rarely  been reported in this species. However, we noted spontaneous gastric carcinomas in 8 sooty mangabeys. Four male and 4 female mangabeys had mild to severe chronic weight loss, with abdominal distention in 5 of 8 animals. At necropsy, 7 of the 8 mangabeys had prominent large ulcerated masses  with severe, diffuse thickening of the pyloric wall at or near the gastric-duodenal junction, which often partially occluded the gastric lumen. Early carcinoma was an incidental finding in one mangabey. Histologically, all of the tumors were classified as adenocarcinomas. Adenocarcinomas  were noncircumscribed with infiltrates of neoplastic epithelial cells, often arranged in acini. In 3 mangabeys, these infiltrates were transmural and invaded surrounding tissue locally. The adenocarcinomas were locally invasive, with metastasis to regional lymph nodes in 2 animals, but widespread  metastasis was not seen. Anisocytosis, anisokaryosis, and high mitotic rates were seen in all 8 tumors. In the samples available, serology and Steiner stain did not detect Helicobacter, and immunohistochemistry failed to reveal Helicobacter or Epstein-Barr virus, 2 potential  causes for human gastric carcinomas.
authors.affiliation: Division of Pathology, School of Medicine, Emory University, Atlanta, Georgia, USA. psharm9@emory.edu
authors.forename: Prachi
authors.initials: P
authors.lastname: Sharma
authors.forename: Joyce K
authors.initials: JK
authors.lastname: Cohen
authors.forename: Katherine S
authors.initials: KS
authors.lastname: Paul
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Courtney
authors.forename: Zachary P
authors.initials: ZP
authors.lastname: Johnson
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Anderson
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000662:veterinary*; D000818:Animals; D000830:Animals, Laboratory; D016665:Cercocebus atys; D017809:Fatal Outcome; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D008992:Monkey Diseases / Q000473:pathology*; D011859:Radiography; D012698:Serologic Tests / Q000662:veterinary; D013270:Stomach / Q000000981:diagnostic imaging; D013274:Stomach Neoplasms / Q000473:pathology / Q000662:veterinary*