Primary adenocarcinoma arising from endometriosis of the rectovaginal septum: a case report.

Adenocarcinomas developing in endometriotic lesions have been reported, most commonly in the ovary. The rectovaginal septum is a rare location of this neoplastic transformation. We report a case of primary adenocarcinoma arising from endometriosis of the rectovaginal septum in a 25-year-old woman presenting with lower abdominal pain and dyspareunia. Diagnostic and treatment modalities were discussed. Immunohistochemical studies of different keratin subtypes and CA125 expression of the tumor cells are of interest for the diagnosis. Preoperative radiation therapy promotes clinical symptoms relief, tumor volume reduction, and better radical surgical approach.