基于二代测序技术比较结直肠癌原发灶与同时或异时性肝转移灶基因突变状态的异同

Comparison of gene mutational status between primary colorectal carcinoma and paired synchronous/metachronous liver metastasis by next-generation

目的:比较研究晚期结直肠癌组织和配对肝转移灶中肿瘤相关基因突变状态的异同。方法:使用二代测序的方法对29对配对的结直肠癌原发灶/同时性肝转移灶及26对原发灶/异时性肝转移灶的KRAS、NRAS、BRAF和PIK3CA突变进行检测。结果:29对结直肠癌原发灶/同时性肝转移灶的突变一致率为93.1%(27/29)。1例原发灶检出KRAS突变,但在其2灶肝转移灶中仅1灶检出相同KRAS突变。1例原发灶存在PIK3CA突变,但在转移灶中未检出。26对结直肠癌组织/异时性肝转移灶的突变一致率为80.8%(21/26),与原发灶/同时性肝转移灶相比差异有统计学意义(P=0.010)。其中,4例原发灶未检出突变,但在转移灶中检出突变。1例原发灶检出KRAS突变,而在转移灶中未检出。结论:同时性肝转移和原发灶间的基因突变一致率较高,而异时性肝转移与原发灶间的基因突变状态可能存在较大差异。

Purpose:To compare the gene mutational status between primary colorectal carcinoma(CRC)and paired synchronous/metachronous liver metastasis.Methods:KRAS,NRAS,BRAF and PIK3 CA mutations were analyzed in 29 patients with primary and paired synchronous liver metastatic CRC,and in 26 patients with primary and paired metachronous liver metastatic CRC using next-generation sequencing(NGS).Results:Same mutation profiles of KRAS,NRAS,BRAF or PIK3 CA between primary and paired synchronous liver metastatic CRCs were observed in 27 of 29 patients(93.1%).Of 2 patients with discordant mutational status,a KRAS mutation was detected in the primary tumor and one of liver metastatic tumors in a patient,but no mutation was observed in the other liver metastatic lesion.A PIK3 CA mutation was observed in primary tumor but not the metastatic tumor in the other patient.Moreover,same mutation profiles between primary and paired metachronous liver metastatic CRCs were observed in 21 of 26 patients(80.8%),which was significantly lower than those in paired primary and synchronous liver metastatic CRCs(P=0.010).Of 5 patients with discordant mutational status,KRAS,NRAS,or PIK3 CA mutations were observed in the metastatic tumors but not the primary tumors in 4 patients,whereas a KRAS mutation was detected in the primary tumor but not the metastatic tumor in 1 patient.Conclusions:The gene mutational discrepancies are more frequently observed in paired primary/metachronous liver metastatic CRCs than paired primary/synchronous liver metastatic CRCs.