Use of adjuvant trastuzumab in women with human epidermal growth factor receptor 2 (HER2)-positive breast cancer by race/ethnicity and education within the National Comprehensive Cancer Network.

Abstract

Trastuzumab for human epidermal growth factor receptor 2 (HER2)-positive breast cancer is highly efficacious yet costly and time-intensive, and few data are available about its use. The authors of this report examined receipt and completion of adjuvant trastuzumab by race/ethnicity and education for women with HER2-positive disease. The National Comprehensive Cancer Network Breast Cancer Outcomes Database was used to identify 1109 women who were diagnosed with stage I through III, HER2-positive breast cancer during September 2005 through December 2008 and were followed for ≥1 year. The authors used multivariable logistic regression to assess the association of race/ethnicity and education with the receipt of trastuzumab and, among those women who initiated trastuzumab, with the completion of > 270 days of therapy. The cohort was 75% white, 8% black, and 9% Hispanic; and 20% of women had attained a high school degree or less. Most women (83%) received trastuzumab, and no significant differences were observed according to race/ethnicity or socioeconomic status. Among the women who initiated trastuzumab, 73% of black women versus 87% of white women (P = .007) and 70% of women with less than a high school education versus 90% of women with a college degree completed > 270 days of therapy (P = .006). In adjusted analyses, black women (vs white women) and women without a high school degree (vs those with a college degree) had lower odds of completing therapy (black women: odds ratio, 0.45; 95% confidence interval, 0.27-074; white women: odds ratio, 0.27, 95% confidence interval, 0.14-0.51). Differences in completing trastuzumab therapy were observed according to race and educational attainment among women who received treatment at National Comprehensive Cancer Network centers. Efforts to assure the appropriate use of trastuzumab and to understand treatment barriers are needed and may lead to improved outcomes. The authors report differences in the rate at which patients complete treatment with trastuzumab according to race and education among women who receive treatment at National Comprehensive Cancer Network centers. Efforts to assure the appropriate use of trastuzumab and to understand treatment barriers are needed and may lead to improved outcomes.