Expression of CD44, EGFR, p16, and their mutual combinations in patients with head and neck cancer: Impact on outcomes of intensity-modulated radiation therapy.

Abstract

Progress in radiation treatment of head and neck squamous cell carcinoma (HNSCC) deserves the studies focused on molecular predictors that would help to enhance individually tailored treatment. p16/epidermal growth factor receptor (EGFR)/cluster of differentiation-44 (CD44) was immunohistochemically analyzed in 165 HNSCC patients. In the entire group and the p16 negative cohort, better 3-year overall survival and locoregional control correlated with p16 positivity, CD44, and EGFR negativity were observed. Combined analysis revealed the worst results in the CD44+/p16-, EGFR+/p16-, and EGFR+/CD44+ groups and in the EGFR+/CD44+ within p16 negative cohort. Multivariate analysis found tumor stage, Karnofsky index, p16, and CD44 as prognostic factors of overall survival and clinical stage, and p16 as a prognostic factor for locoregional control. Clinical stage and Karnofsky index affected overall survival and tumor stage. EGFR affected locoregional control in the p16 negative subgroup. Our study confirmed the negative effect of CD44 and EGFR and the positive effect of p16 on radiotherapy results.