癌组织K—ras基因突变和血清CEA的联合检测预测结直肠癌肝转移的意义

Combined detection of K-ras gene mutation in cancer tissues and carcinoembryonic antigen in serums of patients ,with colorectal cancer to predict liver metastasis

目的观察结直肠癌组织中K-ras基因突变，检测患者外周血清CEA水平，探讨两者与结直肠癌肝转移的关系。方法应用实时荧光定量聚合酶链反应（PCR）方法和基因测序技术检测100例结直肠癌组织中K—ras基因1号外显子12、13密码子突变，化学发光法检测患者血清CEA水平，结合其临床资料分析。结果100例结直肠癌组织中K—ras基因突变者39例（39．0％），其中12号密码子突变31例，13号密码子突变8例。36例肝转移组中K-ras基因突变23例（23／36，63．9％）；64例无肝转移组中K—ras基因突变16例（16／64，25．0％）。36例有肝转移患者外周血清CEA水平为（66．79±127．46）μg/L，其中25例（25／36，69．4％）出现不同程度CEA升高；64例无肝转移患者外周血清CEA水平为（4．93±4．62）μg/L，其中24例（24／64，37．5％）CEA升高。两个指标联合检测，肝转移组的阳性率（22／36，61．1％）明显高于无肝转移组的阳性率（5／64，7．8％），P〈0．01。其预测结直肠癌肝转移的敏感性及特异性分别为61．1％和92．2％。结论K—ras基因突变、血清CEA水平与结直肠癌肝脏转移有密切相关，联合检测癌组织K—ras基因突变和血清CEA水平可预测结直肠癌肝转移。

Objective To detected mutations of K-ras gene in cancer tissues and carcinoembryonic antigen in serums of patients with colorectal cancer, and to find out their correlation with liver metastasis. Methods The specimens of 100 patients with colorectal cancer were collected. Real-time fluorescence quantitative PCR and DNA sequencing were performed in these tissues to detect K-ras gene mutations at codon 12th and codon 13 th of exon 1 ,and carcinoembryonic antigen level in serums were evaluated by radioimmunoassay, and then the results were analyzed with patients＇ clinical pathological data. Results Among the 100 colorectal cancer cases,39 cases （39.0%） were detected pointmutation,and 31 （31.0%） cases were found pointmutation at codon 12,and 8 （8.0%） cases at codon 13. In 36 cases with liver metastasis,23 cases （23/36,63.9%） were found K-ras gene mutations,but only 16 of 64 patients without liver metastasis were found mutated K-ras gene. The difference between the two groups was significant （ P 〈0.05）. CEA level in patients with liver metastasis were （66.79±127.46）μg/L, which was higher than that in those without liver metastasis（4.93±4.62）μg/L. Twenty-five of 36 patients with liver metastasis had a high lever of CEA,24 of 64 patients without liver metastasis did so. The positive rate of combined detection of K-ras gene mutation and CEA lever was 61.1% （22/36） in patients with liver metastasis, which was higher than that in patients without liver metastasis （5/64,7.8 % ）, P 〈 0.01. The sensitivity, specificity of combined detection of K-ras gene mutation and CEA lever in patients with liver metastasis were 61.1% and 92.2%. Conclusion K-ras gene mutation and CEA lever were closely associated with liver metastasis of colorectal cancer. Combined detection of K-ras gene mutation in cancer tissues and CEA lever in serums can predict liver metastasis of colorectal cancer.