实时荧光定量PCR检测结直肠癌腹腔CEA水平及其临床意义的研究

Quantitative detection of CEA level in the peritoneal cavity of colorectal carcinoma patients with real-time RT-PCR and Its clinical significance

目的:应用实时荧光定量PCR技术检测结直肠癌腹腔内CEA水平并探讨其临床意义。方法:2003年5月至2004年3月,收集在日本爱知癌症中心手术107例结直肠癌病例的腹腔冲洗液,每个样本的cDNA应用随机引物合成,并在罗氏的实时荧光定量PCR(LightCycler)上进行定量分析。每个样本同时进行常规细胞学检查。所有病例术后经过平均为1年的随访。结果:CEAmRNA的阳性率和水平均与肿瘤的侵润度(T),分期以及淋巴结转移相关。在一个合理界定值上,CEA和CK-20检测的敏感度与特异度均为100%和100%,而常规的细胞学检查则为33%和100%。结论:CEA定量分析是检测结直肠癌腹腔微转移的敏感和特异的方法,CEAmRNA水平的异常与术后的无瘤生存率显著相关。其临床意义有待于更长期的随访结果。

Objective：The purpose of this study is to detect CEA level in peritoneal cavity of colorectal cancer patients by quantitative Real-time RT PCR method and investigate its clinical significance.Methods：From May 2003 to Mar.2004,peritoneal wash was obtained from 107 patients with colorectal cancer in Aichi cancer center.cDNA was synthesized from mRNA extracted from peritoneal washes by Random primers.Quantification of CEA mRNA was performed on a LightCycler instrument（Roche）with hybridization probe.A part of each peritoneal wash was also examined by conventional cytology.All patients were followed up for a median period of at least 12 months.Results：Both CEA mRNA positive rates and values were significantly correlated with depth of tumor invasion,tumor stage,lymph node status.Sensitivity and specificity of CEA and CK-20 real-time RT-PCR with an appropriate cutoff value were 100%,100%,and 100%,100%,respectively,whereas those of conventional cytology were 33%,and 100%,respectively.Conclusion：CEA mRNA quantifications is sensitive and specific method for detection of micrometastases in the peritoneal washes of colorectal cancer patients.Abnormality of CEA mRNA level in peritoneal washes is correlated with disease free survival for colorectal cancer patients.Further follow-up study is needed to demonstrate the clinical significance of CEA mRNA in peritoneal washes.