ABSTRACT
Purpose To study the status of EGFR mutations and the expression of excision repair cross-complementation group 1 ( ER-CC1) and Ki-67 protein in patients with non-small cell lung cancer (NSCLC) and to examine the relationship between their expression and clinicopathologic features. Methods EGFR mutations were analyzed with DNA sequencing, and the expression of ERCC1 and Ki-67 protein was examined by immunohistochemistry EnVision. The relationship of EGFR mutations with the expression of ERCC1and Ki-67 and the clinicopathological features were analyzed. Results EGFR mutations were detected in 143 (143/291, 49. 1%) of the 291 specimens. EGFR mutations were found more frequently in women, non-smokers and adenocarcinoma. The difference of EGFR muta-tion rate between the histological subtypes according to the IASLC/ATS/ERS classification of lung adenocarcinoma was significantly ( P=0. 008). The mean tumor diameter was smaller in patients with EGFR mutations than in those with wild-type EGFR (P=0. 020). EGFR mutations were not related to age, lymph node metastasis. However, EGFR mutations were not related to the expression of ER-CC1 and Ki-67 protein (P>0. 050). Conclusions EGFR mutation is closely linked to several clinicopathological factors, such as gender, differentiation, and histological subtype. There is heterogeneity of EGFR mutation in patients with NSCLC. EGFR mutations were not related to the expression of ERCC1 and Ki-67 protein.