Prognostic Impact of Immune Microenvironment in Lung Squamous Cell Carcinoma

Abstract

Introduction: We previously reported the prognostic significance of the lung adenocarcinoma immune microenvironment. In this study, we preformed comprehensive analysis of immune markers and their associations with prognosis in patients with lung squamous cell carcinoma. Methods: We reviewed surgically resected, solitary lung squamous cell carcinoma patients (n = 485; 1999-2009) who were randomly split into a training cohort (n = 331) and validation cohort (n = 154). We constructed tissue microarrays and performed immunostaining for CD3, CD45RO, CD8, CD4, FoxP3, CD20, CD68, CXCL12, CXCR4, CCR7, interleukin-7 receptor, and interleukin-12 receptor β2. Overall survival (OS) was analyzed using the log-rank test and the Cox proportional hazards model. Results: Analysis of single immune cell infiltration revealed that high tumor-infiltrating CD10 + neutrophils were associated with worse prognoses in the training cohort (p = 0.021). Analysis of biologically relevant immune cell combinations identified that patients with high CD10 + neutrophil and low CD20 + lymphocyte had a significantly worse OS (5-year OS, 42%) than those with other combinations of CD10 and CD20 (5-year OS, 62%; p < 0.001); this was confirmed in the validation cohort (p = 0.032). For the multivariate analysis, high CD10/low CD20 immune cell infiltration was an independent predictor of OS in both the training cohort (hazard ratio = 1.61, p = 0.006) and the validation cohort (hazard ratio = 1.75; p = 0.043).