Correlation between protein expression and gene amplification of epidermal growth factor receptor in lung cancer

Objective To analyze the expression and gene amplification of epidermal growth factor receptor（EGFR）in lung cancer. Methods Lung cancer cases were collected and reviewed from the archives of our department from 2004 to 2006.Immunohistochemistry（IHC）and fluorescence in situ hybridization（FISH）were performed to detect the expression and gene amplification of EGFR in pure bronchioloalveolar carcinoma（BAC）and conventional adenocarcinoma. Results The EGFR was expressed in 56.52% of conventional adenocarcinomas and in 3.85% of BAC,respectively.EGFR gene was amplified in 45.45% of conventional adenocarcinomas and in 14.81% of pure BAC,respectively.Conventional adenocarcinoma had a higher EGFR expression and gene amplification than pure BAC（P＜0.05）.EGFR gene amplification was correlated with EGFR protein expression（P＜0.005）. Conclusion Protein expression and gene amplification of EGFR can be observed more often in conventional adenocarcinoma than in BAC.Expression of EGFR is frequently accompanied with gene amplification.