Laparoscopic posterior pelvic exenteration for primary adenocarcinoma of the rectovaginal septum without associated endometriosis: A case report

The present report describes a case of laparoscopic posterior pelvic exenteration of a primary adenocarcinoma of the rectovaginal septum (PARS) without associated endometriosis. A 49-year-old woman was admitted to hospital for rectal bleeding. Imaging studies showed a 7-cm solid tumor located in the rectovaginal septum, presenting with invasion to the posterior aspect of the uterine cervix and the anterior rectal wall. The patient received laparoscopic posterior exenteration and rectosigmoid anastomosis followed by chemotherapy. There were no intra- or post-operative complications. Histopathological examination of the neoplastic tissue revealed moderate to severe cytological atypia with bizarre multinucleated cells and prominent mitotic figures. Histopathologically, R0 resection was achieved. No endometriotic lesions were confirmed in the primary tumor or other removed tissues. Immunohistochemistry showed positive staining for cytokeratin (CK)7, cancer antigen 125, vimentin, estrogen receptor and p53, but negative staining for CK20, progesterone receptor, p40 and thyroid transcription factor 1. Based on these findings and on the location of the tumor, the neoplasm was diagnosed as PARS without associated endometriosis, which may have arisen from metaplasia of the embryological Mullerian-duct remnants.