Radiotherapy in laryngeal carcinoma: Can a panel of 13 markers predict response?

Abstract

To find biomarkers associated with response to radiotherapy in laryngeal cancer that can be used together with clinical parameters to improve outcome prediction. In this study, 26 patients irradiated for laryngeal carcinomas with a local recurrence within two years (cases) and 33 patients without recurrence (controls) were included. All pretreatment biopsies were arrayed onto a tissue array. Immunohistochemistry was performed for 13 biomarkers that were selected from the literature as potential predictors for radioresponse in head and neck (HN) cancer: Bcl-2, Bcl-xL, p16, p21, p27, p53, cyclin D1, HIF-1alpha, CA9, COX-2, EGFR, ki-67, and pRB. Univariate logistic regression models showed borderline statistically significant increased relative risks, with positivity for CA9, COX-2, and p53. Goeman's global testing revealed an overall association between outcome and the 13 markers together with clinical variables. The most important markers were CA9 and COX-2. In laryngeal carcinoma, hypoxia and COX-2 overexpression provide a stronger contribution to an increased risk of local recurrence after radiotherapy compared with the well-known candidate markers p53, Bcl-2, and cyclin D1. However, no robust expression profile for the prediction of radioresistance was found.