Goserelin versus CMF as adjuvant therapy for node-negative, hormone receptor-positive breast cancer in premenopausal patients. The GABG IV-A-93 trial

Abstract

534 Background: Increasing evidence supports the use of GnRH analogues as adjuvant treatment in hormone sensitive, premenopausal breast cancer. However, only limited information is available in patients with node-negative disease. Methods: We randomised 771 patients to either goserelin (3.6 mg every 28 days for 2 years; n=393) or 3 cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy (500 mg/m2, 40 mg/m2 and 600 mg/m2, days 1,8 q 29; n=378). Patients' characteristics were well balanced with 26% of the patients being 40 years or younger, 64% having a tumor size below 21mm, 79% having grade 1 or 2 tumors, and 72% receiving breast conserving surgery. 123 events were observed during a median follow up of 4.9 years. Results: The first event of failure (goserelin vs CMF) was an isolated locoregional recurrence (20 vs 18), a distant failure (35 vs 46), and death without recurrence (2 vs 2). Five-year event-free survival rates were 84.4% (95% confidence interval (CI): 80.4% to 88.5%) and 81.0% (95% CI: 76.3% to 85.7%) in the goserelin and in the CMF group, respectively. The estimated hazard ratio (intention-to-treat analysis) of goserelin vs CMF was 0.81 (95% CI: 0.56 to 1.17, P=0.24). Conclusions: Although the results of the trial are still based on relatively few observed events, they add important information to the current attempts of defining the role of medical ovarian ablation with goserelin in premenopausal patients with node-negative, hormonsensitive breast cancer. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration AstraZeneca AstraZeneca AstraZeneca Germany