Carcinoid tumor localized in the liver--two cases report: immunohistochemical and ultrastructural studies.

Two cases of carcinoid tumors, considered to be probably hepatic in origin, occurring in a 53-year-old man and a 69-year-old woman are reported. In both cases no endocrine syndrome appeared, and an alternative primary source of the tumor was not found in case two, despite an intensive search at operation. The neoplasms in both cases were soft, firm, brown-pink and well-encapsulated. They were composed of small uniform cells, that had distinct borders and grew in insular, nests, trabeculae and strands that were separated by a delicate fibrous stroma. Stains of argentaffin and argyrophil showed strong positivity in both cases. The immunohistochemical and ultrastructural studies all demonstrated characteristics of a carcinoid. The postoperative recovery was good. They have remained well 5 years later in case 1 and 3 years in case 2 after surgical treatment. Literature concerning this rare condition is also reviewed.