Relationship between EGFR and KRAS mutations and clinicopathologic features of non-small cell lung cancers / 临床与实验病理学杂志

ABSTRACT

Purpose To explore the relationship between the mutations of epidermal growth factor receptor ( EGFR) and KRAS genes and clinicopathological characteristics in patients with non-small cell lung cancers (NSCLC). Methods Clinical samples from 431 NSCLC patients were obtained for EGFR and KRAS gene analysis. PCR based direct DNA sequencing was used to investigate mutations in exon 18-21 of EGFR gene and codon 12 and 13 of exon 2 of KRAS gene. Results The overall EGFR mutation rate of primary NSCLC was 53. 6% (231/431) in this study cohort and eight cases showed double EGFR mutations. Mutation rates in female and male were 65. 2% (122/187) and 46. 9% (98/209), respectively. The mutation rate was higher in patients with non-smokers and adeno-carcinoma and adenosquamous carcinoma subtypes than in their counterparts (PT, G>A, G>C) , and three patients had codon 13 mutations ( G>A, G>T) . Most of these mutations were G to T transversion (64. 5%, 20/31). Conclusion Polymerase chain reaction-direct sequencing is a reliable and effective method for the detection of the EGFR and KRAS gene mutation in NSCLC patients. The mutation rate of EGFR is higher in Chinese patients, especial-ly in non-smoking female patients with adenocarcinoma.