Incidence of Programmed Cell Death 1 Inhibitor–Related Pneumonitis in Patients With Advanced Cancer

Programmed cell death 1 (PD-1) inhibitor-related pneumonitis is a rare but clinically serious and potentially life-threatening adverse event. Little is known about its incidence across different tumor types and treatment regimens.

To compare the incidence of PD-1 inhibitor-related pneumonitis among different tumor types and therapeutic regimens. DATA SOURCES: A PubMed search through November 10, 2015, and a review of references from relevant articles. For the PubMed search, the following keywords or corresponding Medical Subject Heading terms were used: nivolumab, pembrolizumab, and PD-1 inhibitor. STUDY SELECTION: Twenty-six original articles of PD-1 inhibitor trial results were identified. Among them, 20 studies of melanoma, non-small cell lung cancer (NSCLC), or renal cell carcinoma (RCC) were eligible for a meta-analysis. DATA EXTRACTION AND SYNTHESIS: The data were extracted by 1 primary reviewer and then independently reviewed by 2 secondary reviewers following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Comparisons of the incidence were based on marginal, exact generalized linear models with generalized estimating equations. MAIN OUTCOMES AND MEASURES: Incidence of all-grade and grade 3 or higher pneumonitis and pneumonitis-related deaths.