Trends in utilization of sentinel node biopsy and adjuvant radiation in women ≥ 70

Background and Objectives: Omission of routine axillary staging and adjuvant radiation (XRT) in women ≥ 70 years old with early stage, hormone receptor-positive, clinically node-negative breast cancer has been endorsed based on several landmark studies. We sought to determine how much omission of axillary staging/XRT has been adopted. Methods: Using the National Cancer Data Base, we selected malignant breast cancer cases in women ≥ 70 with ER + tumors, ≤2 cm with clinically negative lymph nodes who underwent breast conservation and had known XRT status in 2005-2015. The use of sentinel lymph node biopsy (SNB) and XRT status was summarized by year to determine trends over time. Results: In total, 57 230/69 982 patients underwent SNB. Of the 12 752 patients in whom SNB was omitted, 6296 were treated at comprehensive community cancer programs. Regarding XRT, 33 891/70 114 received adjuvant XRT. There were no significant trends with regards to patients receiving SNB or those receiving XRT. Conclusion: Since 2005, there has been no change in SNB or XRT for early stage ER + breast tumors. However, there was a difference in omission of SNB based on facility type and setting. Future monitoring is needed to determine if these trends persist following the recently released Choosing Wisely^® recommendations.