Expression of Epidermal Growth Factor Receptor (EGFR) in Non-Small Cell Lung Carcinoma Cytology Specimens

Introduction: Lung Carcinoma is the number one cause of death from cancer. Non-small cell lung carcinoma (NSCLC) consists of three subtypes, namely squamous cell carcinoma (SCC), adenocarcinoma, and large cell carcinoma. Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor that plays an important role in the process of cell growth. EGFR overexpression in NSCLC is often different in each NSCLC subtypes. Overexpression of EGFR protein and EGFR gene amplification can be used as predictor, of success from tyrosine kinase inhibitor therapy to improve prognosis. EGFR protein expression assessment of cytology specimens is rarely, especially in Indonesia. The aim of this study was to evaluate the differences between EGFR in each subtype of NSCLC from cytological specimen.Methods: This is a cross-sectional study consists of 80 cytology cases of NSCLC. In each case, the slide was reviewed and transfer cell was done in clusters of tumor to different new slides. Then the immunocytochemical staining was performed to investigate the expression of EGFR. Results: We found 56 in 80 cases (70%) with positive results, consisting of 24 cases of SCC, 14 cases of adenocarcinoma, and 16 cases NSCLC-NOS (Non Otherwise Specified). Negative EGFR expression obtained in 24 from 80 cases (30%).Conclusion: EGFR expression can be assesed from cytology specimens and there was a statistically significant different of EGFR expression in each subtype of non-small cell lung carcinoma, especially in squamous cell carcinoma of the lung in comparison to the other subtypes. J Indon Med Assoc. 2012;62:331-6Keywords: non-small cell lung carcinoma, epidermal growth factor receptor (EGFR), immunocytochemical.