A cooperative randomized controlled study of adjuvant chemoendocrine therapy for breast cancer in Japan

A randomized trial was carried out in 55 Japanese institutions to examine the significance of postoperative adjuvant chemoendocrine therapy in Stages II and IIIA breast cancer patients after radical mastectomy. A total of 619 patients were entered from November 1982 to November 1984, of whom 554 were eligible. Patients were administered MMC (13 mg/m2) after surgery, and were randomized by the envelope method into either group A (ftorafur, 400 mg/m2/day; 275 patients), or group B (ftorafur, 400 mg/m2/day, and tamoxifen, 20 mg/day; 279 patients). Treatment was continued for 1 year from postoperative day 7. There were no significant differences between the two groups with regard to age, menopausal status, ER status, method of operation, stage, or number of positive lymph nodes. There was also no significant difference between the two groups in the 5-year survival and disease-free survival (DFS) rates (Kaplan-Meier method). Stratification by ER status, nodal status, or menopausal status produced no significant differences between the groups. However, postmenopausal patients and lymph node-positive patients who were also ER-positive showed a significantly higher DFS in group B. Furthermore, group B in ER-positive patients with four or more positive lymph nodes also had a higher survival rate.