Supplementary Material for: Development of Skin Rash Predicts Outcome of Anti-PD-1- and Anti-CTLA4-Based Immune Checkpoint Inhibitor Therapy in Non-Small Cell Lung Cancer or Squamous Cell Carcinoma of the Head and Neck: A Single-Center Analysis

<b><i>Objective:</i></b> We report the spectrum of immune-related adverse effects (irAEs) and outcome observed in a single-center cohort of 100 patients treated with immune checkpoint inhibitors in a routine clinical setting. <b><i>Methods:</i></b> Tumor entities included non-small cell lung cancer (<i>n</i> = 28), head and neck squamous cell carcinoma (<i>n</i> = 28), urothelial carcinoma (<i>n</i> = 7), and others (<i>n</i> = 37). <b><i>Results:</i></b> irAEs were documented in 49% of cases analyzed, and the most frequent manifestation consisted of immune-mediated skin rash (28%), colitis (9%), pneumonitis (8%), hypothyroidism (7%), or hepatitis (6%). Skin rash correlated with improved progression-free survival. <b><i>Conclusion:</i></b> Development of immune-related skin rash was found to correlate with favorable outcome, suggesting its practical feasibility as a potential predictive surrogate marker.