Endometrial carcinoma coexisting with pregnancy, presumed to derive from adenomyosis: a case report.

Endometrial carcinoma coexisting with pregnancy is rarely observed. We report here the case of a 35-year-old woman with an endometrial carcinoma that was diagnosed 6 months after childbirth. Preoperative magnetic resonance imaging (MRI) revealed a cystic mass attached to the uterus, with a papillary projection on the wall of the mass. The patient underwent complete surgical extirpation and five postoperative courses of adjuvant chemotherapy, given that the tumor contents had leaked into the peritoneal cavity when the capsule of the tumor ruptured intraoperatively. Microscopic examination revealed an endometrioid adenocarcinoma in the muscular layer close to the uterine serosa that was presumed to derive from adenomyosis. Further investigation is required to elucidate the pathogenesis of endometrial carcinoma in association with pregnancy and adenomyosis.