Erosive pustular dermatosis–like scalp reaction following cranial radiotherapy in a patient with EGFR-mutant NSCLC treated with amivantamab

Amivantamab, a bispecific monoclonal antibody directed against the epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition factor (MET), has demonstrated significant clinical activity and is increasingly incorporated into frontline regimens for EGFR-mutant non-small cell lung cancer (NSCLC). Its increasing clinical use has, nevertheless, been paralleled by recognition of distinctive cutaneous adverse events, most commonly acneiform eruptions, paronychia, and xerosis among others. We present the first case of an erosive pustular dermatosis (EPD)-like reaction limited to a previously irradiated field in a patient receiving amivantamab for EGFR-mutant NSCLC. This case draws attention to the importance of recognizing EPD-like scalp ulcerations as a potential adverse event in patients receiving amivantamab, events that have not been recognized in clinical trials, particularly in the setting of recent or concurrent radiotherapy.