The immunoexpression of epidermal growth factor receptor in cutaneous squamous cell carcinoma.

Although cutaneous squamous cell carcinomas (cSCCs) account for only 20-25% of non-melanoma skin cancers (NMSCs), they are responsible for most deaths attributable to NMSCs. Apart from SCC seric level, which increases in late-stage disease, no other predictive biomarker for cSCC exists. Epidermal growth factor receptor (EGFR) serves as a predictive biomarker and therapeutic target in numerous malignancies. EGFR immunoexpression is highly elevated in head and neck mucosal SCC. However, its immunoexpression pattern, its relationship with prognosis and survival, and the effect of EGFR targeted therapy in advanced cSCC have not been clarified. We assessed EGFR immunoexpression in 18 cases of cSCC and correlated our findings with the clinicopathological features. Immunohistochemical stainings with anti-EGFR monoclonal antibodies were practiced and the membrane and cytoplasmic immunostaining intensity and quality in the tumors and the non-lesional epithelium were analyzed. Membrane EGFR immunoexpression within the tumors increased with the tumor grade. EGFR overexpression was more frequently found in head and neck cSCCs. We did not find a direct relationship between cytoplasmic EGFR immunoexpression and clinicopathological findings and prognosis. Our results confirm that increased EGFR immunoexpression correlates with aggressive cSCC phenotypes and underline the need for novel treatments for these patients.