Black patients with breast cancer treated with human epidermal growth factor receptor 2 (HER2)-targeted therapies have increased rates of cardiotoxicity leading to incomplete adjuvant therapy compared with white patients, according to a study published in Cancer.
Previous studies have found that various factors such as prior anthracycline therapy, older age, hypertension, history of cardiac dysfunction, and obesity increase the incidence of cardiotoxicity among patients with breast cancer treated with HER2 therapies, but there is a paucity of data on the association between risk and race.
For this retrospective study, researchers assessed the outcomes of 59 black and 157 white patients with HER2-positive breast cancer treated with neoadjuvant or adjuvant trastuzumab with or without pertuzumab. Chemotherapy was initiated in eligible patients with the intent to include at least 1 year of HER2-targeted therapy; if HER2-targeted therapy was initiated, at least 1 year of follow-up data had to be available.
After a median follow-up of 5.2 years, results showed a 12% rate of cardiotoxicity among all study patients, but incidence was nearly quintupled among black women (24%) compared with white women (7%). Black patients also had a significantly higher chance of therapy incompletion compared with white women, and further analysis showed a 96% concordance rate between the failure to complete HER2-treatment and cardiac toxicity.
The authors concluded that black women “may benefit from enhanced cardiac surveillance, cardioprotective strategies, and early referral to cardiology when appropriate.”
Litvak A, Batukbhai B, Russell SD, et al. Racial disparities in the rate of cardiotoxicity of HER2-targeted therapies among women with early breast cancer [published online January 31, 2018]. Cancer. doi: 10.1002/cncr.31260