In a study reported in the Journal of Clinical Oncology, Bostany et al found that the cumulative incidence of cardiac dysfunction reached 15.3% at 15 years from the start of cardiotoxic treatments in breast cancer survivors.
Study Details
The study involved patients at the Next Steps Breast Cancer Survivorship Clinic at the University of Alabama at Birmingham who had completed cardiotoxic therapy and underwent echocardiographic screening every 2 years. Cardiac dysfunction was defined as left ventricular ejection fraction (LVEF) < 50% after cardiotoxic therapy initiation.
Key Findings
A total of 2,808 echocardiograms in 829 breast cancer survivors were assessed. Median age at breast cancer diagnosis was 54.2 years (range = 20.3–86.3 years). Median follow-up was 8.6 years (range = 1.8–39.8 years). Cardiotoxic therapy consisted of anthracyclines in 39.7% of patients, trastuzumab/pertuzumab in 16%, both anthracyclines and trastuzumab/pertuzumab in 6.2%, and radiation therapy alone in 38.1%.
The cumulative incidence of cardiac dysfunction increased from 1.8% at 2 years to 15.3% at 15 years from the start of cardiotoxic therapy. Longitudinal analysis among all patients showed an annual decline of 0.29% in LVEF (P = .009) over 20 years from breast cancer diagnosis.
On multivariate analysis, factors associated with a significantly increased risk of cardiac dysfunction included Black race (hazard ratio [HR] = 2.15, 95% confidence interval [CI] = 1.37–3.38); receipt of cardiotoxic therapies including anthracyclines (HR = 2.35, 95% CI = 1.25–4.4) and anthracyclines and trastuzumab/pertuzumab (HR = 3.92, 95% CI = 1.74–8.85) vs left breast radiation alone; receipt of selective estrogen receptor modulators (HR = 2.0, 95% CI = 1.2–3.33); and history of hypertension prior to cancer diagnosis (HR = 3.16, 95% CI = 1.63–6.1).
Late-onset cardiac dysfunction was most common among patients exposed to anthracyclines and radiation therapy, and early-onset dysfunction was more common among patients exposed to anthracyclines and trastuzumab/pertuzumab.
The investigators concluded, “These findings provide evidence to support echocardiographic surveillance for several years after cardiotoxic therapy and also suggest a need to examine the efficacy of management of cardiovascular risk factors to mitigate risk.”
Smita Bhatia, MD, MPH, of the Institute for Cancer Outcomes and Survivorship, University of Alabama at Birmingham Heersink School of Medicine, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by the Breast Cancer Research Foundation of Alabama. For full disclosures of the study authors, visit ascopubs.org.
