Endometrial carcinoma in Miyagi Prefecture, Japan: histopathologic analysis of a cancer registry-based series and comparison with cases in American women.

Cases of endometrial carcinoma (104) from the Cancer Registry of Miyagi Prefecture, Japan, during the period from 1966--1977 have been reviewed histologically. The most impressive differences between tumors in this low-risk population and those reported in American women are higher frequencies of the mixed adenosquamous histology, myometrial vascular invasion, and lymphoid infiltration within and around the tumors in the Japanese cases. The possible significance of these observations, both clinical and epidemiologic, is discussed in detail.