[Case of proximal-type epithelioid sarcoma of the perineum].

A 31-year-old man was referred to our department for investigation and treatment of a rapidly-growing mass in the perineal region. MRI showed a periurethral tumor in the perineal region measuring 3.5cm in maximum diameter and bilateral inguinal lymph nodes enlargement. Therefore, the tumor was extirpated immediately with bilateral inguinal lymphadenectomy. The pathological examination with immunohistochemistry revealed that the tumor was proximal-type epithelioid sarcoma. Multidisciplinary therapy with irradiation, chemotherapy, and tumor ablation with a microwave tissue coagulator, was not effective for local recurrence and metastasis, and finally he died of progressive disease 14 months after the operation. Epithelioid sarcoma originating from the thigh or trunk is classified into the proximal-type, which shows significantly poorer prognosis than the distal-type that develops in the distal extremities. The proximal-type epithelioid sarcoma of the perineum is rare and, to our knowledge, the present report is the fourth case in the Japanese literatures.