ACUTE ARTERIAL EMBORISM OF THE LOWER EXTREMITY OCCURRED DURING ADMINISTRATION OF MEDROXYPROGESTERONE ACETATE FOR ADVANCED BREAST CANCER

A 66-year-old woman with advanced breast cancer (T3 N3 M1) who had been under treatment with chemotherapy and oral medroxyprogenterone acetate (MPA) 1, 200mg/kg complained of a pain of the right lower extremity on the 57 th day after administration of MPA. Angiography offered a diagnosis of acute arterial embolism of the lower extremity and a thromboembolectomy was performed. After the operation, the dose of MPA was reduced to 600mg/kg and warfarin and an antiplatelet were combinedly used for a prophylactic purpose. Two months later, however, acute arterial embolism of the lower extremity occurred again. Thromboembolectomy and grafting were performed. Oral administration of MPA was discontinued and the patient was under observation while warfarin and the antiplatelet were consistently administered. The patient has been free from recurrence for about 2 years. In this case both oral doses of 1, 200mg/kg and 600mg/kg of MPA induced throombosis and prophylactic oral medication for thrombosis was iniffective. It is suggested that, in the use of MPA, we must remain alert for occurrence of thrombosis irrespective of dose level and discontinue immediately after onset of the disease is noticed.