Analysis of tumor-infiltrating CD103 resident memory T-cell content in recurrent laryngeal squamous cell carcinoma.

BACKGROUND

Recurrent laryngeal squamous cell carcinomas (LSCCs) are associated with poor outcomes, without reliable biomarkers to identify patients who may benefit from adjuvant therapies. Given the emergence of tumor-infiltrating lymphocytes (TIL) as a biomarker in head and neck squamous cell carcinoma, we generated predictive models to understand the utility of CD4, CD8 and/or CD103 TIL status in patients with advanced LSCC.

METHODS

Tissue microarrays were constructed from salvage laryngectomy specimens of 183 patients with recurrent/persistent LSCC and independently stained for CD4, CD8, and CD103 TIL content. Cox proportional hazards regression analysis was employed to assess combinations of CD4, CD8, and CD103 TIL levels for prediction of overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS) in patients with recurrent/persistent LSCC.

RESULTS

High tumor CD103 TIL content was associated with significantly improved OS, DSS, and DFS and was a stronger predictor of survival in recurrent/persistent LSCC than either high CD8 or CD4 TIL content. On multivariate analysis, an "immune-rich" phenotype, in which tumors were enriched for both CD103 and CD4 TILs, conferred a survival benefit (OS hazard ratio: 0.28, p = 0.0014; DSS hazard ratio: 0.09, p = 0.0015; DFS hazard ratio: 0.18, p = 0.0018) in recurrent/persistent LSCC.

CONCLUSIONS

An immune profile driven by CD103 TIL content, alone and in combination with CD4 TIL content, is a prognostic biomarker of survival in patients with recurrent/persistent LSCC. Predictive models described herein may thus prove valuable in prognostic stratification and lead to personalized treatment paradigms for this patient population.