High-dose oral medroxyprogesterone acetate in heavily pretreated patients with metastatic breast cancer.

Fifty heavily pretreated postmenopausal patients with advanced breast cancer were treated with oral medroxyprogesterone acetate (1 g) daily for 1-18 months. Eight patients (16%) responded to treatment for periods up to 18 months and in an additional eight patients (16%) the disease stabilized for up to 10 months. Thirty-two patients (64%) developed adverse effects and eight (16%), all of whom had extensive pulmonary metastases, died a respiratory-related death thought possibly to have been brought on or accelerated by treatment. Only eight patients (16%) experienced increased appetite, weight gain, feeling of wellbeing, or improved performance status. We conclude that medroxyprogesterone acetate is useful in patients with advanced metastatic disease but should be restricted to carefully selected patients and used only with extreme caution in patients with underlying cardiovascular or respiratory disease. Its major application probably lies in the benefit it confers earlier in the disease.