Racial and Ethnic Differences in Long-Term Adverse Radiation Therapy Effects Among Breast Cancer Survivors

Abstract

Breast and skin changes are underrecognized side effects of radiation therapy for breast cancer, which may have long-term implications for quality of life (QOL). Racial and ethnic disparities in breast cancer outcomes, including long-term QOL differences after breast radiation therapy, are poorly understood. We conducted a cross-sectional survey study of patients from the Texas Cancer Registry who received diagnoses of stage 0-II breast cancer from 2009 to 2014 and treated with lumpectomy and radiation therapy; 2770 patients were sampled and 631 responded (23%). The BREAST-Q Adverse Effects of Radiation overall score and subindices measured the effect of radiation therapy on breast tissue. Multivariable logistic regression evaluated associations of demographic and treatment characteristics with outcomes. The median age was 57 years (IQR, 48-65), median time from diagnosis to survey response 9 years (IQR, 7-10), and the cohort included 62 Asian American or Pacific Islander (9.8%), 11 American Indian or Alaskan Native (AIAN) (1.7%), 161 Black (25.5%), 144 Hispanic (22.8%), and 253 White (40.1%) patients. Mean BREAST-Q Adverse Effects of Radiation score was worse for AIAN patients (-22.2; 95% CI, -39.9 to -4.6; P=.01), Black patients (-10.8; 95% CI, -16.1 to -5.5; P < .001), and Hispanic patients (-7.8; 95% CI, -13.0 to -2.5; P=.004) compared with White patients, age <50 compared with ≥65 (effect size -8.6; 95% CI, -14.0 to -3.2; P=.002), less than a college education (-5.8; 95% CI, -10.0 to -1.6; P=.01), bra cup size of D/E versus A/B (-5.3; 95% CI, -9.9 to -0.65; P=.03), and current smokers (-11.3; 95% CI, -18.3 to -4.2; P=.002). AIAN, Black, and Hispanic patients reported worse changes in skin pigmentation, telangiectasias, dryness, soreness, and/or irritation compared with White patients. AIAN, Black, and Hispanic patients reported substantially worse long-term breast and skin QOL outcomes after radiation therapy. Additional work is needed to understand these differences and how to alleviate them.