Systemic immune-inflammation index predicts prognosis in patients with different EGFR-mutant lung adenocarcinoma

Lung cancer is the most common type of cancer worldwide with a high mortality rate. The specific tyrosine kinase inhibitors of epidermal growth factor receptor (EGFR) have made enormous strides in non-small-cell lung cancer (NSCLC) treatment. The novel systemic immune-inflammation index (SII), a parameter that integrates lymphocytes, neutrophils, and platelets, has been found to play the vital role of a marker for predicting survival and recrudescence in various tumors. We retrospectively examined 102 patients with different EGFR-mutant lung adenocarcinomas. Survival analysis was performed using the Kaplan-Meier method with the log-rank test. Cut-off points were identified using the receiver operating characteristic curves with the maximum log-rank values. The Cox proportional hazards regression, expressed as p value, hazards regression, and 95% confidence interval, was conducted to assess the prognostic values of variables in overall survival (OS)/ progression-free survival (PFS). Lower SII was associated with prolonged survival in patients with different EGFR mutant lung adenocarcinomas in both variable and multivariable analyses. SII before treatment was a powerful indicator for the PFS and OS of patients who received the first-generation EGFR-TKI.