Trends in Utilization of Hypofractionated Whole Breast Radiation in Breast Cancer: An Analysis of the National Cancer Database.

PURPOSE Utilization of hypofractionated radiation (HR) as a component of breast conserving treatment (BCT) in breast cancer is relatively low in the U.S. despite studies demonstrating its efficacy and guidelines supporting its use from the American Society for Radiation Oncology (ASTRO) in 2011 and 2018. Little is known regarding national trends in uptake and factors associated with uptake of HR in the U.S. since the 2011 ASTRO guidelines. METHODS We performed a retrospective review of the National Cancer Database (2012-2016) on patients undergoing BCT. Logistic regression modeling was used to identify relationships between patient, hospital, and tumor factors with the use of HR or traditional radiation (TR). RESULTS A total of 259,342 cases of BCT were identified with 60% (n=155,447) undergoing TR and 40% (n=103,895) undergoing HR. There was an increase in use among patients meeting 2011 ASTRO criteria from 26.2% in 2012 to 67.0% in 2016. The odds of utilization of HR increased with year of diagnosis, patient age, higher median income, private insurance, treatment at an academic center, travel distance to treatment >20 miles, smaller tumors, lymph node negative disease, and without use of chemotherapy (p-values <0.0001, Table 1). CONCLUSION Guidelines supporting the use of HR in BCT have been associated with a dramatic increase in utilization of HR in the U.S. However, there are substantial, identifiable disparities in the uptake of HR at patient and facility levels. By understanding which patient populations are at risk of not receiving the benefit of this therapy, we can improve our utilization of HR in the U.S., potentially leading to reduced healthcare costs and increased patient satisfaction.