A case-control study on risk factors for uterine endometrial cancer in Japan.

A case-control study of 143 Japanese women with uterine endometrial cancer and 143 individually age-matched controls was conducted to assess the risk factors for endometrial cancers in Japan. Among the characteristics studied, the following factors were significantly greater in the cases than in the controls: nulliparity (odds ratio for parity 1-3 and > or = 4 versus nullipara are 0.40 and 0.02, respectively), obesity (odds ratio: 2.73), hypertension (odds ratio: 2.4), diabetes mellitus (odds ratio: 6.30), and a personal medical history of cancer (odds ratio: 3.06). The present study showed that Japanese women have the same risk factors for endometrial cancer as those reported in Western countries. The recent increase in the incidence of endometrial cancer in Japan may be largely attributed to the decrease in parity.