title: Case report: spontaneous hemangiosarcoma in the pancreas of a Fischer rat.
abstract: Spontaneous hemangioma or hemangiosarcoma is sometimes found in the viscera and soft tissue of rats and mice. However, there is no report of the tumor occurring in the pancreas of rats. We report a pancreatic hemangiosarcoma in a 109-wk-old, male Fischer 344 rat, which was used in the control group of a carcinogenicity study. The tumor destroyed and compressed the normal pancreatic tissue and displayed a high density in terms of the numerous capillaries and strands of endothelial tumor cells. A reticulin stain revealed a dense network formation. The frequency of proliferating cell nuclear antigen-positive staining showed active proliferation of the tumor cells. Immunohistochemically, some of the tumor cells stained positive with factor VIII-related antigen, and ultrastructurally, Weibel-Palade bodies were rarely observed in the cytoplasm of the tumor cell. From these findings, the tumor was diagnosed as a hemangiosarcoma that occurred naturally in the pancreas.
authors.affiliation: Mitsubishi Chemical Safety Institute Ltd., Kashima-gun, Ibaraki-ken, Japan. okatsuta@ankaken.co.jp
authors.forename: O
authors.initials: O
authors.lastname: Katsuta
authors.forename: T
authors.initials: T
authors.lastname: Doi
authors.forename: Y
authors.initials: Y
authors.lastname: Okazaki
authors.forename: Y
authors.initials: Y
authors.lastname: Wako
authors.forename: M
authors.initials: M
authors.lastname: Tsuchitani
mesh_terms: D000818:Animals; D006394:Hemangiosarcoma / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D007150:Immunohistochemistry; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D051381:Rats; D011916:Rats, Inbred F344; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D018809:Proliferating Cell Nuclear Antigen; D014841:von Willebrand Factor