[Hormonotherapy of metastatic breast cancer with tamoxifen and medroxyprogesterone acetate. Randomized trial comparing alternating sequences with successive applications]

Abstract

Sixty-eight women with metastatic breast cancer occurring less than five years positives after the treatment of the primary tumour, with estrogens and/or progesterone receptors (EPR), were randomized. Sixty-four patients were available for evaluation of efficacy and toxicity. Thirty patients received treatment A: tamoxifen 30 mg per day alternating every two weeks with medroxyprogesterone acetate (MPA) 1 000 mg per day orally. Thirty-four received treatment B: tamoxifen 30 mg per day and after relapse, high dosage of MPA alone. The distribution of the evaluable metastasis and the value of the ER are the same in the two groups. The total responses or the responses by metastatic site were as follows: complete response, one case in each treatment group, partial response, 6 and 10 cases, no change, 14 and 17 cases and progressive disease, 9 and 6 cases respectively. The duration of the response was the same in the two groups with a median of 6 months (extremes of 30 and 19 months). Among the patients under protocol B, 19 received MPA after failure of tamoxifen: eight responded (3 partial responses and 5 no change). Toxicity was slight but 2 treatments in group A were discontinued. Alternated sequential hormonal treatment is theoretically attractive for these patients with known and positive EPR but it is not more efficient than the two hormonotherapies applied successively.