Endometrioid stromal sarcomas arising from ovarian and extraovarian endometriosis: report of two cases and review of the literature.

Endometrioid stromal sarcomas arising from endometriosis are rare tumors. Two cases from our institution are presented and the literature is reviewed. The patients tend to be nulliparous. Presentations usually are related to the symptoms of a pelvic mass. However, extraovarian origin was frequently accompanied by hemorrhage. The tumors are usually of low histologic grade. Among 18 patients with ovarian origin, only 2 were reported dead of disease. However, 5 of 13 patients with extraovarian origin died mostly as a result of recurrent disease. Deaths generally occurred within 3 years of diagnosis. The efficacy of chemotherapy, radiotherapy, or hormonal therapy in the adjuvant or recurrent setting cannot be determined from the available reports.