Myocarditis in Cancer Patients: A Review of an Emerging Problem in Cardio-Oncology

Abstract

Patients with cancer have a multitude of etiological factors for developing myocarditis. Classical or conventional chemotherapy, radiation therapy, and, more recently, immunotherapy have all been described as possible etiologies of myocarditis. Furthermore, patients with cancer are immunosuppressed and more susceptible to bacterial and viral infections that can cause myocarditis. This narrative review addresses the many possible causes of myocarditis in patients with cancer. Particular emphasis will be given to immune checkpoint inhibitor (ICI)-induced myocarditis. ICI myocarditis generally affects male patients, over the age of 50, who are being treated for lung cancer, melanoma, or renal cell carcinoma and have multiple comorbidities. Clinical manifestations present early, with elevated troponin and electrocardiogram changes. The case fatality rate is high. Treatment consists of discontinuation of the offending ICI and corticosteroid therapy. Myocarditis due to cyclophosphamide, anthracyclines, 5-fluorouracil, cisplatin, carboplatin, proteasome inhibitors, immunomodulators, tyrosine kinase inhibitors, and radiation therapy will also be addressed.