Dedifferentiated extrauterine adenosarcoma responsive to chemotherapy.

Extrauterine adenosarcoma, a low-grade mixed mesodermal tumor, is an uncommon neoplasm. Little information is available regarding the efficacy of treatment of tumors not amenable to surgical resection. Our patient's pelvic adenosarcoma progressed despite multiple attempts at surgical excision over an 8-year period. Hormonal therapy with medroxyprogesterone acetate and tamoxifen did not alter the frequency of recurrence. However, aggressive cisplatin-ifosfamide-based combination chemotherapy produced a dramatic response in the metastatic tumor in the liver. Cisplatinum, doxorubicin, and ifosfamide may thus be active against this tumor. Regional arterial infusion, when feasible, may enhance response.