Ovarian remnant syndrome (ORS) is a rare, but well-known gynecological complication, most often induced by difficult bilateral salpingo-oophorectomy (BSO) procedures that leave residual ovarian tissue on the pelvic wall. The most common preexisting conditions for this complication include endometriosis, pelvic inflammatory disease and prior abdominal surgery. The residual ovarian tissue may eventually cause malignant development. A total of 12 cases of malignant and benign tumors (clear cell adenocarcinoma in 1 case, mucinous-type tumors in 2, endometrioid-type tumors in 5, adenocarcinoma in 3 and border serous neoplasia in 1) and 21 benign cysts developing from an ovarian remnant have been described in the literature to date. Endometriosis, known to increase the risk of ovarian cancer, predisposes patients to ORS, with an incidence rate of 30 to 50% in ORS patients with ovarian carcinoma. Although the true incidence of ORS remains unknown, when endometriotic adhesions are diagnosed during BSO, the possibility of ORS and subsequent ovarian malignant transformation may mandate complete surgical resection.
Keywords: clear cell carcinoma; endometrioid adenocarcinoma; endometriosis; ovarian remnant syndrome; serous cystadenoma.