SAN ANTONIO – Clinical trials have shown a clear benefit for preventing breast cancer recurrence with aromatase inhibitor (AI) therapy following 5 years of tamoxifen. Yet the optimal duration for additional AI therapy following 5 years of endocrine therapy with tamoxifen, an AI, or sequential therapies is not known, according to Michael Gnant, MD, from the Medical University of Vienna.
In the (Arimidex) was no more effective than 2 additional years following the standard 5 years of initial endocrine therapy in postmenopausal women with hormone receptor–positive (HR+) breast cancer., Dr. Gnant and his colleagues reported that 5 years of additional therapy with anastrozole
at the San Antonio Breast Cancer Symposium, Dr. Gnant notes that, although some patients may still benefit from 5 years of additional therapy, the trial results suggest that most patients can be spared from such adverse events as risk for fractures associated with three additional and evidently unnecessary years of therapy.
The ABCSG-16 study was supported by AstraZeneca. Dr. Gnant disclosed research funding, honoraria, and travel funding from the company and others.