Overexpression of EGFR in esophageal squamous cell carcinomas - A new biological target in cancer therapy.

Abstract

Esophageal squamous cell carcinoma (ESCC) is the predominant type of esophageal cancer in the Asian belt. These cancers show poor prognosis with an overall 5-year survival rate less than 19%. Exploring new molecular therapeutic targets such as epidermal growth factor receptor (EGFR) could be the corner stone of new curative treatment. The present study was done to analyze the overexpression of EGFR in different grades of ESCC and explore its role as a diagnostic and theranostic marker in ESCC. In this retrospective study, 50 formalin-fixed paraffin-embedded blocks of ESCCs diagnosed from 2014 to 2019 were retrieved. The biopsies were subjected to immunohistochemistry staining of EGFR. The intensity of the membrane staining was reviewed and scored. Compared with various intrinsic and extrinsic factors using Chi-square test, scores more than 2+ were considered as overexpression. Majority (84%) specimens demonstrated overexpression of EGFR where high-grade ESCCs had greater overexpression rates compared to low-grade ESCC (P < 0.05). By targeting the EGFR molecules, anti-EGFR drugs could block their signals and stop the growth and spread of ESCCs especially high-grade tumors while harming the normal cells as little as possible. A clinical trial using anti-EGFR monoclonal antibodies will help in the long run to develop immunotherapy drugs.