Protein expression of epidermal growth factor receptor in laryngeal squamous cell carcinoma index tumors correlates with diagnosis of second primary tumors of the upper aero-digestive tract

Background. Field cancerization is a feature of HNSCCs. No biological marker in the index tumor has correlated with second primary tumor (SPTs) development. Changes in MDM-2 and epidermal growth factor receptor (EGFR) expression are known to be early neoplastic changes in HNSCC. EGFR expression is correlated with clinical outcomes. This study has assessed the predictive correlation of MDM-2 and EGFR protein expression with clinicopathological parameters and occurrence of SPTs in HNSCC. Methods. Using immunohistochemistry, 106 patients who were treated for primary laryngeal squamous cell carcinoma were investigated for expression of MDM-2 and EGFR. Results. Positive expression of MDM-2 and EGFR was found in 51 of 106 (48.1%) and 82 of 106 (77.4%) cases, respectively. EGFR expression was found to correlate with diagnosis of new primary tumors (P = 0.003), disease-free survival (P = 0.008), as well as overall survival (P = 0.003). MDM-2 expression correlated with nodal relapse (P = 0.03). Conclusions. SPTs relate to poor prognosis in HNSCC, indicating that closer clinical surveillance of this patient group would be beneficial. Examination of the expression of EGFR by the primary tumor could have potential clinical benefits because this study suggests that it may become a vital biomarker for patients who are most at risk of developing SPTs.