Ensuring equitable adjuvant treatment may alleviate the racial disparity in breast cancer mortality; yet little is known about factors that facilitate or impede treatment. This study assesses and examines racial/ethnic disparities in adjuvant breast cancer treatment offered, accepted, and initiated.
The primary data came from a population-based study that included 989 females living in Chicago, age 30 to 79 years, who were diagnosed with first primary breast cancer in 2005–2008. Logistic regression using model-based standardization was used to estimate age-adjusted risk differences and path analyses were conducted to help explain the disparities.
Chemotherapy treatment (CT) guidelines changed during the study period, and the association between race/ethnicity and treatment differed depending on which guideline was used to determine CT-eligibility. Among those for whom CT became discretionary, minority patients were more likely than non-Hispanic (nH) White patients to receive a CT recommendation but this was largely explained by tumor differences. There were no discernible racial/ethnic differences in radiation treatment (RT) recommendation and acceptance. However, among all RT-eligible patients, minority patients were less likely than nH White patients to receive RT (0.75 versus 0.74, p=0.01). This was explained by the higher use of mastectomy and lower breast tumor knowledge among minority patients. Compared to nH White patients (0.94), minority patients (0.80) were less likely to receive a recommendation for hormonal treatment (p=0.00). Tumor knowledge appears to be an important contributor of this disparity as well.
Mastectomy patients may not be receiving guideline-adherent RT. In addition, a patient’s breast tumor knowledge may be protective against treatment underuse. These may present important avenues for disparity-reducing interventions