Current overview of EORTC clinical trials with tamoxifen

Based upon concepts derived from estrogen receptor studies, a phase II exploratory trial was conducted where tamoxifen (NSC-180973) was administered concomitantly with cytotoxic chemotherapy in postmenopausal patients with advanced breast cancer. Chemotherapy was composed of two 28-day cycles given alternatively. Cycle A consisted of adriamycin and vincristine, and cycle B consisted of cyclophosphamide, methotrexate, and 5-fluorouracil. Fifty-five patients were fully evaluable. Complete remissions were obtained in 13 (24%) and partial objective remissions in 27 (49%). The overall remission rate was 73%. Toxic side effects ranged from mild to severe. The most significant were nausea and vomiting (most patients), weakness and pain (two thirds of the patients), and hematologic changes (half of the patients). It is concluded that the present combination of endocrine and cytotoxic therapy represents one of the most effective currently available treatments of advanced breast cancer. In an early clinical trial of tamoxifen in premenopausal patients with advanced breast cancer, two objective remissions, lasting 5 and 9+ months respectively, were obtained in ten patients treated. Tamoxifen is worthy of further assessment in premenopausal patients.