Maintenance treatment with medroxyprogesterone acetate in patients with advanced breast cancer responding to chemotherapy: results of a randomized trial

The purpose of this randomized phase III trial was to study whether medroxy progesterone acetate (MPA) maintenance treatment prolongs the time to progr ession in advanced breast cancer patients responding to an induction chemot herapy. Patients with progressive advanced breast cancer previously untreat ed with anthracylines and progestins were given epirubicin (30 mg/m(2)) and ifosfamide (2 g/m(2)) on days 1 and 8 at 3-weekly intervals. Patients with out disease progression after 6 cycles of chemotherapy were randomly assign ed to receive, until progression, either no treatment or MPA at a daily tot al dose of 500 mg. Ninety patients were randomized: 46 to the MPA arm and 4 4 to the observation arm. Median time to progression was longer in the MPA arm: 4.9 months versus 3.7 months in the intent-to-treat analysis (p=0.02), and 4.9 months versus 3.0 months in the secondary efficacy analysis (p=0.0 12). Seven patients were removed from MPA due to side effects. The changes in patient-rated quality of life scores were similar in both groups. The me dian length of survival from randomization was 17.4 months for patients rec eiving MPA and 18.3 months for patients randomized to observation (p=0.39). In conclusion, in patients with advanced breast cancer achieving remission or non-progression with 6 cycles of epirubicin and ifosfamide chemotherapy , MPA maintenance treatment led to a significant, though modest, prolongati on of the time to progression without affecting overall survival of the stu dy patients.