Disparities in Refusal of Adjuvant Radiation for Breast-Conserving Therapy in the USA

Breast-conserving therapy (BCT) with lumpectomy and adjuvant radiation offers equivalent outcomes to mastectomy among many patients with early-stage (T1-2N0) breast cancer. Nevertheless, certain populations may experience barriers to receiving BCT and may refuse radiation therapy (RT). We utilized the National Cancer Database (NCDB) to assess factors associated with refusal of adjuvant RT among patients receiving lumpectomy.

We performed a retrospective cohort analysis of women ≥ 18 years old diagnosed with cT1-2N0M0 disease in the NCDB from 2004 to 2017 who underwent lumpectomy for removal of the primary tumor. Multivariable logistic regression was used to calculate the adjusted odds ratios (ORs) of refusing RT despite physician recommendation in association with relevant sociodemographic variables. All statistical testing was two sided, and the results were deemed statistically significant at p < 0.05.

Of the 580,192 women who underwent lumpectomy, 29,527 (5.09%) refused recommended RT. In the adjusted analysis, Black (OR 1.07 [95% confidence intervals (CI) 1.02-1.12], p = 0.006) and Native Hawaiian or Pacific Islander (OR 1.35 [95% CI 1.04-1.74], p = 0.025) women were more likely to refuse RT than White women. Older age, higher educational attainment, greater distance from treatment facility, uninsured status, greater comorbidity burden, and higher clinical stage were also associated with refusal of RT (all p < 0.05).

Disparities persist in the refusal of recommended adjuvant RT among patients with early-stage breast cancer. Efforts are needed to further understand underlying reasons for treatment refusal, to promote patient education informed by cultural humility, and to reduce barriers to RT access.