Vulvar extrauterine endometrial stromal sarcoma: A case report and literature review.

Endometrial stromal sarcoma (ESS) is an extremely rare neoplasm accounting for only 0.2% of all uterine malignancies and for 15-26% of primary uterine sarcomas. The annual incidence of ESS is 1-2 per million women. Herein, to the best of our knowledge, we present the first reported case of ESS of the vulva in a 50-year-old female presenting with per vaginal spotting over a period of three months. Her past surgical history included a subtotal hysterectomy and left salpingo-oophorectomy for uterine fibroids ten years previously. On examination, a 3.5×3×2 cm cystic mass was found in the right labia majora. The mass was excised and the diagnosis of endometrial stromal sarcoma was made. Subsequent metastatic workup was negative and the patient was started on megestrol acetate. She has remained disease free with no signs or symptoms of recurrent or advanced disease for 28 months.