KRAS基因状态对晚期结直肠癌一线化疗联合贝伐珠单抗疗效的预测价值

目的研究KRAS基因状态对晚期结直肠癌（mCRC）给予一线化疗联合贝伐珠单抗疗效的预测价值。方法选取mCRC病人216例，进行KRAS基因检测，给予一线化疗联合贝伐珠单抗的治疗方案。拟定4~8周期化疗。每4周期化疗后，通过结肠镜、腹部B超、增强CT等检查，根据实体瘤疗效评价标准（RECIST 1.0），观察KRAS基因突变状态与治疗的应答率（RR）、无进展生存时间（PFS）和总生存时间（OS）的相互关系。结果mCRC病人中34.2%存在KRAS基因突变。KRAS基因突变组转移至肺与肝多于KRAS基因野生组（P < 0.05和P < 0.01）。KRAS基因突变型与野生型比较，低分化型多于中/高分化型（P < 0.01）。2组总体RR、PFS差异均无统计学意义（P>0.05）。KRAS基因突变组比基因野生型组OS减少，但差异无统计学意义（P>0.05）。2组出现中性粒细胞减少、消化道反应、疲乏感、蛋白尿等不良反应情况类似（P>0.05）。Cox生存分析模型显示，KRAS基因突变不能作为PFS和OS的预后因素（P>0.05）。结论mCRC给予一线化疗联合贝伐珠单抗治疗，KRAS基因突变状态对疗效尚无预测作用。

Predictive value of KRAS gene status on the effects of the first-line chemotherapy combined with bevacizumab treating metastatic colorectal cancer

ObjectiveTo investigate the predictive value of KRAS gene status on the effects of the first-line chemotherapy combined with bevacizumab treating metastatic colorectal cancer(mCRC).MethodsKRAS gene in 216 patients with mCRC was detected, and the patients were treated with the first-line chemotherapy combined with bevacizumab for 4~8 cycles.After every 4 cycles of chemotherapy, the patients were detected using colonoscopy, abdominal B-ultrasound and enhanced CT.The relationships between the mutation status of the KRAS gene, and response rate(RR), pogression free survival(PFS), total survival(OS) in all patients were analyzed according to the evaluation criteria of solid tumor efficacy.ResultsKRAS gene mutations were found in 34.2% of patients with mCRC.The number of patients with tumor transferring to the lung and liver in KRAS gene mutation group was more than that in KRAS gene wild-type group(P < 0.05 and P < 0.01).Compared to the KRAS gene wild-type group, the case of low differentiation type tumor in KRAS gene mutation group was more than that of the medium/high differentiation type tumor(P < 0.01).The differences of the RR and PFS between two groups were not statistically significant(P>0.05).The OS in KRAS gene mutation group decreased compared to the wild-type group, but the difference of which between two groups was not statistically significant(P>0.05).The neutropenia, gastrointestinal reaction, fatigue, proteinuria and other adverse reactions in two groups were similar.The Cox survival analysis model showed that the KRAS gene mutation was not set as a prognostic factor of PFS and OS(P>0.05).ConclusionsThe mutation status of the KRAS gene does not play a prognostic role in mCRC patients treated with the first-line chemotherapy combined with bevacizumab.