PARIS--New analyses from the mega-databank of the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) have confirmed that both ovarian ablation and polychemotherapy make a small but real difference in survival, Professor Richard Peto, of the University of Oxford's ICRF Clinical Trial Service Unit, said at the Sixth International Congress on Anti-Cancer Treatment (ICACT).
Previous reports from this overview of 200 trials involving 100,000 women have spotlighted a similar benefit with tamoxifen(Drug information on tamoxifen) (Nolvadex), but have found no survival advantages for adjuvant radiotherapy vs no radiotherapy or for mastectomy vs breast-conserving surgery.
Speaking on behalf of the EBCTCG, Professor Peto said that 10-year overall survival was 60.6% for breast cancer patients under the age of 50 who had undergone ovarian ablation, as compared with 56.2% for those who had not. This difference was maintained for up to 15 years, when overall survival was 52.9% with ovarian ablation vs 47.4% without (P = .004).
"The differences in recurrence-free survival were even more definite, so the idea that breast cancer in women under 50 is not sensitive to hormone therapy just isn't true," he said. "It's not a large difference, but it's as big as the effect of streptokinase(Drug information on streptokinase) and aspirin(Drug information on aspirin) in reducing mortality after myocardial infarction."
A 5% edge in overall survival also emerged for patients who had been treated with multiple chemotherapeutic agents, relative to those who had not received polychemotherapy. Professor Peto said that this benefit was independent of the particular multiple chemotherapeutic regimen used.
"You can actually get double the benefit by using double treatment," he continued, noting that chemotherapy combined with tamoxifen yielded better results than either approach used alone.
[Editors' Note: Professor Peto's report on the latest EBCTCG metaanalysis of tamoxifen trials appeared on page 1 of the January, 1996, issue of Oncology News International.]