Relationship between RAS,BRAF gene mutations and HER2 gene amplification and clinicopathology and prognosis of colorectal cancer / 中华普通外科杂志

ABSTRACT

Objective:To investigate the relationship between RAS, BRAF gene mutations and HER2 gene amplification and clinicopathology and prognosis of colorectal cancer.Methods:The clinical data of 268 patients with colorectal cancer were retrospectively analyzed. KRAS, NRAS and BRAF gene mutations and the HER2 gene amplication were detected.Results:The mutation rates of KRAS, NRAS and BRAF were 53.4% , 2.6% and 3.0%, respectively. The amplification rate of HER2 was 6.7%. KRAS gene mutation tended to occur in the right side colon and rectal cancers( χ2=10.824, P=0.004). BRAF gene mutation mainly occurred in the right side colon cancer ( P=0.044). HER2 gene amplification tended to occur in colorectal cancer patients with RAS/BRAF wild-type ( OR=0.322,95% CI0.117-0.887, P=0.027). Univariate analysis showed that the progress-free survival of colorectal cancer patients with RAS mutation was significantly shorter than that of the patients with wild( χ2=6.153, P=0.013), and there was no significant difference in overall survival time( χ2=1.938, P=0.164).The progress-free survival and overall survival time were shorter in BRAF mutation than in the wild type( χ2=8.090, P=0.004; χ2=11.125, P=0.001). Multivariate analysis showed that BRAF gene mutation was independent risk factor for survival of colorectal cancer patients ( HR=3.536,95% CI1.305-9.583, P=0.013). Conclusion:BRAF gene mutations was independent risk factor for poor prognosis of colorectal cancer patients.