A total of 44 extrahepatic bile duct
carcinomas comprising 13 well-differentiated
adenocarcinomas, 25 moderately differentiated
adenocarcinomas, and 6 poorly differentiated
adenocarcinomas were examined histologically and immunohistochemically for
somatostatin,
gastrin, and
glicentin. Argyrophil cells, argentaffin cells, and
somatostatin- and
gastrin-immunoreactive cells within the
tumor were detected in 46.2%, 15.4%, 23.1%, and 15.4% of well-differentiated
adenocarcinomas, and in 16.0%, 8.0%, 12.0%, and 4.0% of moderately differentiated
adenocarcinomas, respectively. No
tumor tissues of poorly differentiated
adenocarcinomas contained endocrine cells. A statistically significant difference in the frequency of argyrophil cells was observed between well and poorly differentiated
adenocarcinoma. The incidence of argyrophil cells and
somatostatin-immunoreactive cells in nonneoplastic mucosa adjacent to well-differentiated
adenocarcinoma was higher than in that adjacent to poorly differentiated
adenocarcinoma.
Glicentin-immunoreactive cells could not be demonstrated either in
tumor tissue or in nonneoplastic mucosa of the extrahepatic bile duct. With reference to the histogenesis of extrahepatic bile duct
carcinoma, it was assumed from these results that the development of well-differentiated
adenocarcinoma might be closely related to the occurrence of endocrine cells and that poorly differentiated
adenocarcinoma might develop from ordinary mucosa.