Oral medroxyprogesterone acetate in the treatment of metastatic breast cancer.

Thirty-nine evaluable, postmenopausal patients with metastatic breast carcinoma were treated with medroxyprogesterone acetate administered orally at daily doses of 800 mg/day in 29 patients and 400 mg/day in 10 patients. One patient experienced a complete remission and 16 had partial remissions for an objective remission rate of 44%. There was no apparent difference in response between the two dose levels. Median remission duration was 8 months, and median survival for the whole group is expected to exceed 18 months. Increased appetite (66%) and weight gain (97%) were the most common side effects, followed by fluid retention, muscle cramps, and increased blood pressure. Performance status improved and white blood cell and platelet counts increased in the majority of patients. Medroxyprogesterone acetate is an effective hormonal agent in the treatment of metastatic breast cancer.