中文摘要：

目的： 观察结直肠癌患者门静脉血液、原发肿瘤组织及相应肝转移灶K-ras基因突变情况,分析三者的一致性,探讨结直肠癌患者门静脉血K-ras基因突变与肝转移关系.方法： 实时荧光定量PCR技术和基因测序技术检测59例结直肠癌患者门静脉血液、原发肿瘤组织及15例肝转移灶K-ras基因突变,结合其临床资料分析.结果： 59例结直肠癌组织中20例（33.9%）发现K-ras基因突变,18例（30.5%）结直肠癌患者的门静脉血中也发现K-ras基因突变,15例肝转移灶中8例（53.3%）发现K-ras基因突变,与原发癌组织的基因突变率差异不明显（P〉0.05）.18例门静脉血存在K-ras基因突变者,其相应的肿瘤组织中均发现K-ras突变.结直肠癌组织中无K-ras基因突变者,患者门静脉血未发现基因突变.8例肝转移灶发现K-ras基因突变者门静脉血亦均有K-ras基因突变,7例肝转移灶无K-ras突变者门静脉血也无K-ras突变.原发肿瘤组织、相应门静脉血和5例同时性、2例异时性肝转移灶的K-ras基因突变类型基本一致（即K-ras基因12密码子GGT突变为GAT或GTT）,1例异时性肝转移灶K-ras基因突变类型为13密码子GGC突变为GAC.原发癌组织与门静脉血K-ras基因突变一致率为96.6%（57/59）,肝转移灶与门静脉血K-ras基因突变情况基本一致,但突变类型有不同.结论： 结直肠癌的原发灶、门静脉血及肝转移灶的K-ras基因突变较为一致,原发癌组织和门静脉血均有K-ras基因的突变,预示着肿瘤可能通过血行转移至肝脏.

英文摘要：

AIM ： To evaluate the concordance of K - ras oncogene mutations in primary colorectal tumors, liver metastases and portal vein blood of the patients with colorectal cancer, and to find out the relationship between mutated Kras oncogene and liver metastases in colorectal cancer. METHODS： Fifty - nine patients with colorectal cancer were screened for the mutations of K - ras oncogene in the tissue samples of primary tumors, portal vein blood and liver metastases （only 15 cases of the 59 patients） by real -time fluorescence quantitative PCR and DNA sequencing. The results were also analyzed with the clinical data of the patients. RESULTS ： Point mutations of K - ras were found in the primary tumors in 20 （33.9%） of the 59 patients with colorectal cancer, and 18 （30. 5% ） of the 59 patients in their portal vein blood. K -ras mutations in 8 （53.3%） of 15 liver metastases were also detected. No significant difference among the rates of K- ras mutation in primary tumor tissues, portal vein blood and related liver metastases was observed （ P 〉 0. 05 ）. Eighteen cases with mutated K- ras gene in portal vein blood showed the mutations in primary tumor tissues The patients without mutated K - ras gene in primary tumor tissue also showed negative mutation of K - ras in the portal vein blood. The mutated K -ras gene in both liver metastase and portal vein blood were detected in 8 of the 15 cases with liver metastases, and no mutated K - ras gene was detected in the others with liver metastases. The main types of K - ras mutations found in primary tumors, liver metastases （5 simultaneous, 2 metachronous） and portal vein blood were GGT to GAT and GGT to GTr at codon 12. A K-ras mutation at codon 13 （GGC to GAC） was found in one case with metachmnous liver metastases~ The rate of concordance of K- ras status between primary tumors and portal vein blood was 96. 6%. Detection of K- ras mutations in liver metastases was accordant with that in portal vein blood, but the type of K - ras mutation wa