BackgroundSintilimab-induced rash is a significant clinical challenge in lung cancer treatment, often necessitating therapy interruption or discontinuation and thereby compromising patient outcomes. The underlying mechanisms of this adverse event remain poorly understood. This study aimed to investigate potential predictive biomarkers and mechanisms of sintilimab-induced rash through metabolomic profiling.MethodsA total of 55 patients with lung cancer who received sintilimab were enrolled, inclu