Relationship between the mutations of K-Ras and EGFR gene and the clinicopathological features of non-small cell lung cancer

ZHANG Jiexia; LI Shiyue; ZHAN Yangqing; OUYANG Ming

Abstract：Objective To investigate the relationship between the mutations of K-Ras and epidermal growth factor receptor ( EGFR) gene and K-Ras gene and clinicopathological features in Chinese patients with non-small cell lung cancer( NSCLC) . Methods From July 2011 to August 2013, 381 cases of NSCLC patients with both EGFR and K-Ras mutations tested in the First Affiliated Hospital of Guangzhou Medical University were retrospectively enrolled in the study. All pathological specimens were tested for twenty-one mutations in EGFR 18-21 exon and six mutations in K-Ras 12,13 codon by amplification refractory mutation system( ARMS) . The clinicopathological features of patients were analyzed according to the mutation status of EGFR and K-Ras. Results Gene mutation of K-Ras was tested in 21 cases, including 20 cases 12 codon mutation and 1 case 13 codon mutation. Gene mutation of EGFR was tested in 146 cases, including 4 cases of 18 exon G719S mutation, 52 cases of 19 exon delection mutation, 3 cases of 20 exon delection muta-tion, 85 cases of 21 exon mutation ( 81 cases of L858R and 4 case of L861Q) and two dual gene mutation. K-Ras mutation was more frequently happened in male patients than in female patients ( 6?8% vs. 2?5%, P=0?018) . EGFR mutations were related with gender, smoking history, TNM stage, systemic metastases and pathological type( P<0?05) . Binary Logistic regression shown that pathological type and gender were closely related to EGFR mutation( P<0?05) . Conclusion EGFR mutation was common in Chinese patients with NSCLC, and was related to adenocarcinoma. However, K-Ras mutation was rare and more commonly happened in male patients with NSCLC. More studies should be conducted to investigate the relationship between clinical features and EGFR and K-Ras mutation.