Is there a Prognostic Role of Focal Adhesion Kinase and CD8 in Squamous Cell Head and Neck Cancer Treated with Radiotherapy?

The prevalence of relapses in advanced squamous cell head and neck cancer (SCHNC) is significant, and so is treatment morbidity. There is persistent need for reliable biomarkers in order to better personalize treatment. The purpose of the present study was to evaluate prognostic significance of focal adhesion kinase (FAK) and CD8 expression in human papillomavirus (HPV) negative SCHNC treated with radiotherapy. FAK and CD8 expression was evaluated by immunohistochemical staining. A total of 62 tissue samples were assessed. High expression of FAK was determined in 37.1% and high expression of CD8 in 25.8% of study patients. Patients with high expression of FAK had significantly more relapses than patients with low FAK expression (p=0.04). FAK and CD8 expression had no significant impact on overall survival (OS) (p=0.44 and p=0.48, respectively) and relapse free survival (RFS) (p=0.21 and p=0.31, respectively). However, patients with high expression of FAK and low expression of CD8 had the worst 5-year OS (38.7%) and 5-year RFS (44.3%). Patients with low expression of FAK had significantly less relapses. The prognostic role of FAK and CD8 expression in SCHNC patients treated with radiotherapy was not proven.