CHICAGO – New data from the TAILORx trial are welcome news for women with HR-positive, HER2-negative, axillary node–negative early-stage breast cancer and their oncologists caught in the gray area surrounding the need for adjuvant chemotherapy.
Results of the noninferiority phase 3 trial—the largest adjuvant breast cancer treatment trial ever conducted—show that among the 6,711 women with an intermediate Oncotype DX Breast Recurrence Score (11-25), those who received only endocrine therapy and skipped adjuvant chemotherapy did not have worse invasive disease-free survival than counterparts who received both (hazard ratio, 1.08; P=.26).
The 9-year rate of invasive disease–free survival was 83.3% with endocrine therapy alone and 84.3% with both chemotherapy and endocrine therapy, and the pattern was essentially the same for freedom from any recurrence and distant recurrence, and overall survival.
The findings are practice changing, according to lead study author Joseph A. Sparano, MD, associate director for clinical research at the Albert Einstein Cancer Center and Montefiore Health System in New York, and vice-chair of the ECOG-ACRIN Cancer Research Group.
In a video interview at the annual meeting of the American Society of Clinical Oncology, he discussed implications of the new data for decision making, results of interaction analyses showing that one size does not fit all and certain women with intermediate recurrence scores do derive benefit from adjuvant chemotherapy, as well as plans to use the tumor samples for future analyses on those that do recur.