Abstract: | An Extremely rare case with the endometrial carcinoma induced by the prolonged (for 20 years) use of IUD (Oota Ring) was reported. The patient was a 57-year-old woman who visited our clinic claiming spotting, and the cancer was revealed by a D & C examination. Since no high risk factors for endometrial carcinogenesis were noted in this patient, it was inferred that prolonged use of IUD played an important role as a cocarcinogen. In particular, the mechanical action of the inserted IUD was thought to be responsible for carcinogenesis. The inflammatory reactions observed in the tumor tissues were considered to be the secondary changes induced by carcinoma. |