Should women with early breast cancer under 40 years of age have a routine 21-gene recurrence score testing: A SEER database study.

Abstract Purpose To investigate the effect of 21-gene recurrence score (RS) on chemotherapy-decision making and prognosis in breast cancer patients aged Methods Using the Surveillance, Epidemiology, and End Results program, we included patients aged Results We included 2721 patients in this study. According to TAILORx cutoffs, 352 (12.9%), 1814 (66.7%), and 555 (20.4%) patients were classified as low-, intermediate-, and high-risk cohorts, respectively. The 21-gene RS categories were associated with the probability of receiving chemotherapy, with 7.1%, 33.4%, and 77.1% of patients in low-, intermediate-, and high-risk cohorts treated with chemotherapy, respectively (P Conclusions 21-gene RS has clinical implications for young breast cancer patients with respect to optimizing chemotherapy-decisions. Despite increasing rates of chemotherapy receipt in young patients, more studies are needed to determine the definitive effect of chemotherapy in young patients with three RS categories.