Cardiac Outcomes Following Adjuvant Radiation Therapy in Triple-Negative Breast Cancer Patients With Prior Autoimmune Myocarditis

This study highlights the potential for late-onset cardiac events or symptoms in patients with TNBC with prior autoimmune myocarditis treated with adjuvant RT. Although most maintained stable cardiac function, a subset developed late-onset ventricular dysfunction or new symptoms despite low mean heart doses and pembrolizumab discontinuation. These findings warrant further investigation of the etiology, including the possibility that immune modulation from RT plays a role.