Comparative study in the expression of p53, EGFR, TGF-α, and cyclin D1 in verrucous carcinoma, verrucous hyperplasia, and squamous cell carcinoma of head and neck region

Verrucous carcinoma (VC) is a locally invasive, nonmetastasizing variant of squamous cell carcinoma (SCC) with distinct clinical and histologic features. Molecular alterations detectable by immunohistochemical analyses in VC have not been extensively studied. This study investigates the expression of p53, epidermal growth factor receptor (EGFR), transforming growth factor-alpha (TGF-alpha), and cyclin D1 in VC, verrucous hyperplasia (VH), and classic SCC of the head and neck. Twenty-six cases of VC, 12 cases of SCC of various differentiations, and 4 cases of VH were studied. Formalin-fixed, paraffin-embedded archival material was used for immunohistochemistry (avidin-biotin immunoperoxidase technique) to study the expression of oncogenes and their tumor markers. Identification of p53 protein was found in 100% of VH, 88% of VC, and 100% of SCC. EGFR expression was noted in 25% of VH, 54% of VC, 40% of well-differentiated SCC (WDSCC), and 100% of moderately and poorly differentiated SCC (MDSCC/PDSCC). TGF-alpha was detected in 25% of VH, 88% of VC, 80% WDSCC, and 100% of MDSCC/PDSCC. Cyclin-D1 expression was seen in 75% of VH, 35% of VC, 100% of WDSCC, 67% of MDSCC, and 50% of PDSCC. Correlation between the level of expression of all markers and the grade of this group of squamous lesions revealed statistically significant correlation coefficients for p53 and EGFR but not for TGF-a and cyclin D1.