Liu QQ, et al. - Utilizing the Surveillance, Epidemiology, and End Results database with known hormone receptor (HoR) and human epidermal growth factor receptor 2 (HER2) status, researchers carried out a retrospective cohort study to assess the significance and benefit of radiotherapy (RT) according to different molecular subtypes in young early-stage breast cancer patients. Between 2010 and 2013, they identified female patients (aged 18-45) received RT treatment and diagnosed with stage T1-3, N0-3, M0 primary breast cancer. Multivariable-adjusted analyzes exhibited that HER2 in breast cancer patients was a significant factor favorable for RT benefit. Findings suggested that RT could provide significant survival benefits in young early-stage breast cancer patients with luminal-A, luminal-B and especially HER2-enriched female patients. The outcomes enabled clinicians to predict the benefits of RT for breast cancer patients and improve evidence-based treatment.