A clinical trial of megestrol acetate in advanced breast cancer

Abstract

Megestrol acetate is a potent oral progestin with anti‐estrogenic activity. It was given in doses of 40‐mg tablets after each meal and at bedtime (160 mg daily) to 30 patients with progressing disseminated breast cancer. It was well tolerated; no toxic reactions were observed. Seven patients < 23.3%) met the criteria of improvement as employed by the Cooperative Breast Cancer Group, and had a mean objective remission of 5.5 months. Most of the seven responders to megestrol acetate had prior trials with a sex hormone, and one or more cytotoxic compounds; three had a modified Cooper's five‐drug combination. The circumstance that this progestin has demonstrated utility late in the sequence of therapy bodes well for this compound having a useful role in the treatment of advanced breast cancer.