The Impact of Adjuvant Radiotherapy Combined With Targeted or Immunotherapy on the Heart in Breast Cancer.

With the increasing adoption of combination therapies involving targeted therapy, immunotherapy, and radiotherapy in breast cancer treatment, the potential cardiotoxicity risks have emerged as a major clinical concern. This article reviews key clinical trial evidence from recent years, including studies published up to March 2025, focusing on the short-term and long-term cardiovascular impacts of combination therapies, aiming to provide clinically relevant guidance for decision-making. Current clinical studies indicate relatively low rates of acute cardiac adverse events during the treatment period. However, long-term follow-up data reveal that patients receiving high-dose radiotherapy (cardiac radiation dose ≥ 25 Gy) show a significantly increased 10-year risk of cardiovascular events. Emerging evidence suggests that cardiotoxicity exhibits delayed onset characteristics and significant interindividual variability. Therefore, future research should prioritize long-term cardiac monitoring in combined treatment regimens and actively explore effective strategies to mitigate cardiotoxicity risks. Proposed approaches include establishing comprehensive dynamic monitoring systems integrating radiomics and biomarkers, optimizing radiotherapy dosing to minimize cardiac damage, and developing myocardial protective agents, ultimately achieving optimal balance between treatment efficacy and patient safety.