Early-Onset Chronic Drug-Induced Cardiomyopathy in a Pediatric Patient With Ewing Sarcoma

Drug-related cardiomyopathy, most notably that caused by anthracyclines, significantly impairs the quality of life in childhood cancer survivors (CCS). In contrast to adults, early-onset chronic cardiomyopathy following chemotherapy is relatively uncommon in CCS, and the underlying pathophysiological mechanisms remain poorly understood. We present a case of a nine-year-old boy who developed severe acute heart failure and subsequent cardioembolic stroke due to early-onset anthracycline-induced cardiotoxicity following treatment for Ewing sarcoma. Whole-exome sequencing revealed two candidate single-nucleotide polymorphisms: HAS3 rs2232228 and RAC2 rs13058338, which may be implicated in the genetic predisposition to anthracycline-related cardiomyopathy. This case highlights the importance of considering early-onset cardiotoxicity in pediatric patients and supports further research into genetic risk-based screening and prevention strategies.