Background Breast conserving surgery (BCS) and adjuvant hormonal therapy (HT) without radiation therapy (RT) is an acceptable approach for older women with early stage, estrogen receptor (ER) positive breast cancer. Toxicity and compliance remain issues with HT. Adjuvant RT alone may have better compliance, but its efficacy in the absence of HT is unclear. We aim to assess patterns of adjuvant therapy and survival outcomes among older women with early stage, ER positive (ER+) breast cancer. Methods The National Cancer Data Base (NCDB) was used to identify 130,194 women age ≥65 years with invasive ER+, node negative breast cancer diagnosed between 2004 and 2015. All patients underwent BCS. Kaplan‐Meier survival curves were used to examine overall survival (OS). The association between adjuvant therapy and OS was assessed in multivariable Cox proportional hazards regression models. Results Unadjusted 5/10‐year OS rates were 90.0%/64.3% for HT and RT, 84.2%/54.9% for RT alone, 78.7%/44.5% for HT alone, and 71.6%/38.0% for no treatment; p
In this cohort study of 130,194 women age ≥65 years with invasive ER+, node negative breast cancer who underwent breast conserving surgery, radiation (RT) with hormonal therapy (HT) was associated with the highest 5 and 10‐year survival rates (90.0% and 64.3%, respectively). Compared to patients receiving HT alone, those receiving RT alone had improved unadjusted and adjusted survival rates.