Abstract 2954: Overexpression of specific genes in surgical margins of head and neck squamous cell carcinoma patients may predict a significantly increased risk of recurrence

Abstract

Head and Neck Squamous Cell Carcinoma (HNSCC) is a high incidence and mortality disease. Despite significant improvements in therapeutic strategies, the overall survival rate in 5 years is around 50%. The presence of microscopic tumor in surgical margins is associated with treatment failure, locoregional recurrence and reduction of overall survival. For this reason, it is vital to ensure tumor-free surgical margins in these patients. Commonly, the extension of surgical resection is determined during the surgery through a low sensitivity histological exam of frozen tissue stained with Hematoxylin and Eosin. Since genetic alterations precede histological alterations, molecular markers may be useful to identify cells that have already started malignant transformation without having developed a histological phenotype that could be detected through conventional histopathological techniques. Also, novel molecular techniques make possible to obtain molecular data of surgical margins in a period of time compatible with the surgery, helping the surgeon in the resection of positive molecular margins in the same surgery and thereby reducing the risk of local recurrence. This study aimed to determine the gene expression pattern of specific markers in HNSCC surgical margins and verify the utility of these markers in detecting the presence of tumor cells in these tissues and predict tumor recurrence. Nine selected genes were evaluated and a panel of 5 genes showed a high specificity and good sensibility. Overexpression of at least one of these genes was found in 50% (23/46) of histologically free surgical margins analyzed and was associated with local recurrence. Patients with positive molecular margins were 7.3-fold more likely to have local recurrence. These preliminary results suggest that the approach used in this analysis is more sensible than traditional histopathological exams and could be useful for the intraoperative diagnosis of the presence of tumor cells in HNSCC surgical margins and as an informative tool to identify and monitor subsets of HNSCC patients with an increased risk of recurrence and consequently reduced survival. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2954.