Abstract

Background: Whether chemotherapy is beneficial to all breast cancer patients is still up for debate.
Clients and techniques: Tamoxifen for 5 years or Tamoxifen plus three concurrent courses of cyclophosphamide, methotrexate, and 5-fluorouracil (‘classic’ CMF) chemotherapy, either early, delayed, or both were the two treatment options given to 1212 postmenopausal patients with node-positive disease in the International Breast Cancer Study Group (IBCSG) trial VII. Tamoxifen alone or three cycles of adjuvant traditional CMF administered before tamoxifen were the two treatment options offered to 1669 postmenopausal individuals with node-negative illness in IBCSG trial IX. According to the main tumor’s oestrogen receptor (ER) content, results were evaluated.
Results: In comparison to tamoxifen alone, adding CMF early, delayed, or both decreased the probability of relapse in patients with node-positive, ER-positive illness by 21% (P = 0.06), 26% (P = 0.02), and 25% (P = 0.02), respectively. When CMF was administered to patients with node-negative, ER-positive tumours before tamoxifen, there was no difference in their disease-free survival.
Conclusions: For patients with node-positive, endocrine-responsive breast cancer, CMF given concurrently(early, delayed, or both) with tamoxifen was more efficacious than tamoxifen alone, supporting late delivery of chemotherapy even after starting tamoxifen. For individuals with node-negative, endocrine-responsive illness, however, consecutive CMF and tamoxifen proved unsuccessful.