Endometriosis-associated tumor at the inguinal site: report of a case diagnosed during pregnancy and literature review.

Malignant degeneration of endometriosis in the inguinal region is rare, and has only been reported in six cases in the literature, none of which was detected during pregnancy. We present the first case of endometriosis-associated adenocarcinoma in the inguinal region in a 34-year-old woman who was 35 weeks' pregnant. The tumor rapidly grew in the last 2 months of pregnancy as a left inguinal painful mass. Histologically, the tumor consisted of a moderate-to-poorly differentiated ovarian-type endometrioid adenocarcinoma arisen in endometriosis foci of both typical and atypical type. Elective labor induction was performed at 35 weeks of gestation and subsequently the patient underwent a conservative surgical treatment followed by chemotherapy. This case raises issues on the management of such an unusual tumor both during and outside pregnancy.