A Critical Review of the Impact of SMARCA4 Mutations on Survival Outcomes in Non-Small Cell Lung Cancer

Abstract

This critical review investigates the impact of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4 (SMARCA4) mutations on survival outcomes in non-small cell lung cancer (NSCLC) through an analysis of 21 peer-reviewed articles. Survival analyses across this review demonstrated consistently worse outcomes for SMARCA4-mutated vs. SMARCA4 wild-type NSCLC patients, specifically emphasizing class 1 truncating mutations as an independent factor for poor overall survival. In addition, this review explores the clinicopathologic characteristics of SMARCA4 mutations and their impact on various treatment modalities, including immune checkpoint inhibitors (ICIs) both with and without Kirsten rat sarcoma viral oncogene homolog (KRAS) co-mutations. The potential ineffectiveness of ICI treatment in NSCLC is explored through the impact of SMARCA4/KRAS co-mutations on the tumor microenvironment. Moreover, this NSCLC review consistently reported statistically worse overall survival outcomes for SMARCA4/KRAS co-mutations than SMARCA4 wild-type/KRAS-mutated cohorts, extending across ICIs, chemo-immunotherapy (CIT), and KRAS G12C inhibitors. Designing prospective clinical SMARCA4-mutated or SMARCA4/KRAS co-mutated NSCLC trials to evaluate targeted therapies and immunotherapy may lead to a better understanding of how to improve cancer patients’ outcomes and survival rates.