Proximal-type epithelioid sarcoma of vulva - Case series of a rare tumor.

Epithelioid sarcoma (ES) is rare and aggressive soft tissue neoplasm characterized by tumor cells showing epithelioid morphology and immunohistochemically, characteristic loss of INI1/ SMARCB1 in most cases. The proximal-type ES usually involves the deeper soft tissues of the vulva or perineum is an extremely rare entity with diagnostic challenges. Surgery is the mainstay of treatment in localized diseases. Radiation and chemotherapy are used in the advanced and metastatic setting, however, their role in the adjuvant setting is uncertain. Anthracycline and gemcitabine-based chemotherapy are given in metastatic and recurrent tumors. We report 4 cases of ES treated over a period of 6 years at our center. All the cases initially presented at a local hospital with vulvar swelling with a benign mimic (3/4) or squamous cell carcinoma (1/4). The median age of diagnosis was 34 years (range 17-80). The diagnosis was established with epithelioid morphology of tumor cells and immunohistochemically characteristic loss of INI1/SMARCB1 in all cases. 3 cases were treated with upfront surgery and two of them received adjuvant radiotherapy. One case received upfront palliative therapy due to lung metastasis at the time of presentation. On median follow-up of 24 months (2-63), 2 cases were disease-free. One case had a recurrence in the lungs and chest wall after a disease-free interval of 63 months. She underwent surgical excision of metastatic deposits, however developed second lung recurrence after 3 months and is being treated with Adriamycin-based chemotherapy. All patients are alive at the last follow-up.