Impact of Rash Development for Patients with Non-Small Cell Lung Cancer Receiving PD-1/PD-L1-Based Immune Checkpoint Inhibitor Therapy

<bold>Background:</bold> Immune-related skin rash is common in patients receiving PD-1/PD-L1-based immune checkpoint inhibitor therapy. This study aimed to explore whether development of rash is predicative of outcomes in patients with non-small cell lung cancer receiving PD-1/PD-L1-based immune checkpoint inhibitor therapy. <bold>Methods:</bold> Relevant data from 299 patients with non-small cell lung cancer receiving PD-1/PD-L1-based immune checkpoint inhibitor therapy during April 2019 to June 2021 were retrospectively collected and analyzed. All patients were followed with the primary endpoints of overall survival and progression-free survival. The Kaplan-Meier curve and Cox regression model were used for data analysis. <bold>Results:</bold> Skin rash was observed in 47 (15.72%) patients. During a median follow-up time of 40 (IQR 30-49) months, 187 and 82 patients developed progression and died, respectively. The Kaplan-Meier curve showed that the overall survival (42 [IQE 33-50] vs 31 [IQR 22-35], P=0.008) and progression-free survival (30 [IQE 23-36] vs 18 [IQR 13-25], P=0.004) were significantly longer in those with skin rash than those without. However, development of skin rash does not have independent prognostic significance for overall survival (HR=1.11 [95% CI 0.89-1.43], P=0.48) and progression-free survival (HR=1.23 [95% CI 0.93-1.50], P=0.18) in the fully adjusted Cox model. <bold>Conclusions:</bold> Although the development of skin rash may indicate robust immune response, it does not have independent prognostic significance for patients with non-small cell lung cancer receiving PD-1/PD-L1-based immune checkpoint inhibitor therapy.