Exercise for the mitigation of cancer therapy-related cardiac dysfunction in breast cancer patients treated with anthracyclines: a systematic review and meta-analysis.
PURPOSE: Cancer therapy-related cardiac dysfunction (CTRCD) is a significant concern for breast cancer patients undergoing anthracycline-based chemotherapy. Although exercise has been proposed as a cardioprotective strategy, existing reviews have largely examined heterogeneous cancer populations receiving varied treatments, leaving a gap in the evidence base focused exclusively on anthracycline-induced CTRCD. This systematic review and meta-analysis aimed to address that gap by evaluating the effects of long-term exercise on key CTRCD markers in breast cancer patients treated exclusively with anthracyclines. METHODS: A comprehensive search of PubMed, Scopus, Cochrane Central Register of Controlled Trials, and Web of Science was conducted for randomized controlled trials including breast cancer patients undergoing anthracycline-based chemotherapy, receiving long-term exercise interventions (≥ 12 weeks, ≥ 1 session/week) compared to usual cancer care, and reporting at least one of the following outcomes: left ventricular ejection fraction, global longitudinal strain, cardiac troponin I, cardiac troponin T, or N-terminal prohormone of brain natriuretic peptide. RESULTS: Six randomized controlled trials involving 360 participants were included. Exercise significantly attenuated cardiac troponin I elevation compared to controls (SMD = -0.50; 95% CI, -0.93 to -0.06; p = 0.02). No statistically significant between-group differences were observed for left ventricular ejection fraction, global longitudinal strain, cardiac troponin T, or N-terminal prohormone of brain natriuretic peptide. CONCLUSION: The cardioprotective role of exercise during anthracycline treatment remains uncertain, though the attenuation of cardiac troponin I elevation suggests a potential protective signal warranting further investigation through larger, standardized trials employing advanced assessment modalities and longer follow-up periods.