Disparities in the Use of Postmastectomy Radiation Therapy for Inflammatory Breast Cancer.

Abstract

Although radiation therapy improves locoregional control and survival for inflammatory breast cancer (IBC), it is underused in this population. The purpose of this study was to identify variables associated with the underuse of postmastectomy radiation therapy (PMRT) for IBC. Using the 1998 to 2011 National Cancer Data Base, we identified 8273 women who underwent mastectomy for nonmetastatic IBC. We used logistic regression modeling to determine the demographic, tumor, and treatment variables associated with the underuse of PMRT. Although the use of PMRT increased over time, a total of 30.3% of our cohort did not receive PMRT. On multivariate analysis, variables associated with the underuse of PMRT for IBC included the following (all P<.05): Medicare insurance (odds ratio [OR] = 0.70), annual income <$34,999 (<$30,000: OR=0.79; $30,000-$34,999: OR=0.82), cN2 and cN0 disease (cN2: OR=0.71; cN0: OR=0.63), failure to receive chemotherapy and hormone therapy (chemotherapy: OR=0.15; hormone therapy: OR=0.35), treatment at lower-volume centers (OR=0.83), and treatment in the South and West (South: OR=0.73; West: OR=0.80). Greater distance between patient's residence and radiation facility was also associated with the underuse of PMRT (P=.0001). Although the use of PMRT for IBC has increased over time, it continues to be underused. Disparities related to a variety of variables impact which IBC patients receive PMRT. A concerted effort must be made to address these disparities in order to optimize the outcomes for IBC.