Background: Lung cancer is the most common type of cancer worldwide with an estimation of 1.82 million new cancer cases diagnosed; and it is the leading cause of cancer-related deaths. Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase identified as being highly expressed in cancer cells including lung cancers. The aim of the study is to determine the EGFR mutation status in non-small cell lung cancer (NSCLC) patients to investigate the association between the EGFR mutation status and clinicopathological characters of patients.
Methods: The tissue samples of the lung cancer patients were collected bronchoscopically. The EGFR mutations of 70 NSCLC patients were determined by the immunohistochemistry (IHC).
Results: EGFR mutations were present in 24 cases (34.29%), including 19 (79.13%) cases of exon 19 and five (20.83%) cases of exon 21 mutation. EGFR mutations were frequently associated with adenocarcinoma and non-smoker. Statistically significant association of EGFR mutations with adenocarcinoma subtypes and non-smokers was found (P < 0.05); and no significant association of EGFR mutation with the age of the patient (P = 0.4647) and the stage (P = 0.4578) of the tumor was found. When we compared between these two mutations, no significant association with age (P=0.614) and smoking status (P=0.127) was found in this study.
Conclusions: EGFR mutations were significantly associated with female sex, non-smoker and adenocarcinoma subtypes. The analysis of EGFR mutation by the IHC method is a potentially useful tool to guide clinicians for personalized treatment of NSCLC patients of adenocarcinoma subtype.
Keywords: EGFR; Immunohistochemistry; Lung cancer; Non-small cell lung carcinomas.