Clinical features and prognostic biomarkers of patients with the rare SMACRA4 gene mutation in non-small cell lung cancer

Background: Non-small cell lung cancer carrying SMARCA4 mutations is characterized by a high degree of malignancy and a poor prognosis. Due to the rarity of the population and the lack of a series of studies, the characteristics of the population with NSCLC and SMARCA4 mutations are not yet clear. Methods: : The retrospective study collected data on 224 patients with tumors eligible for enrollment from December 2020 to July 2022. Among them, 26 developed SMARCA4 mutations, and 20 were eligible for inclusion in the specimen,with survival follow-up until April 2023. Clinical features, pathological characteristics, molecular features, and the role in the prognosis of SMARCA4 mutations were analyzed. The TCGA database was used to screen and obtain 481 NSCLC-SMARCA4-Mut samples for clinical characterization. Results: : In TCGA, 283 patients with NSCLC-SMARCA4-Mut were ≥60-75 years old (58.84%), with a median age of 67 years. There were 312 males (64.86%) and 169 females (35.13%), with 374 smokers (77.75%). The origin sites of lung cancer were 277 (57.59%) in the upper lobe. Among the 20 clinical SMARCA4-Mut patients included, 12 (60%) were males and 8 (40%) were females, with a median age of 63 years. Through intergroup prognostic correlation analysis, the prognosis of SMARCA4-Mut patients was significantly worse than that of SMARCA4-Wt patients (P = 0.024). The positive expression of NapsinA was better in PFS1 and OS in SMARCA4-Mut (P = 0.016, P = 0.037). We used the ROC curve to predict PFS1 and OS of NapsinA in the Mut group with statistical significance (AUC = 0.829, P = 0.025, AUC = 0.814, P = 0.031). Conclusion: NSCLC-SMARCA4-Mut has a worse clinical prognosis. NapsinA-positive expression in SMARCA4-Mut patients was significantly associated with prolonged PFS1 and OS.