小细胞肺癌外周血EpCAM阳性循环肿瘤细胞检测的临床意义

Clinical significance of EpCAM positive circulating tumor cells in peripheral blood of small cell lung cancer

目的:探讨以上皮细胞黏附分子(EpCAM)为标志物的荧光定量聚合酶链反应(qRT-PCR)方法检测小细胞肺癌(SCLC)外周血循环肿瘤细胞(CTCs)的临床意义。方法:通过前瞻性随访研究,用qRT-PCR对50例初治SCLC患者外周血中EpCAM信使核糖核酸(mRNA)表达水平及拷贝数进行检测,来评价SCLC患者外周血中EpCAM^(+)-CTCs的拷贝数及变化与临床特征及预后之间的关系。结果:50例患者治疗前EpCAM^(+)-CTCs的拷贝数为130.89~10971.43 copies/μL。治疗前不同临床病理特征和分期的患者CTCs拷贝数差异无统计学意义(P>0.05)。化疗2个周期后不同性别、吸烟状态的患者EpCAM^(+)-CTCs拷贝数有差异(P<0.05)。治疗前、治疗2个周期后CTCs拷贝数以及治疗前后CTCs减少比例均不能预测1年生存率。拷贝数及治疗后减少比例高低与总生存(OS)无关(P>0.05)。结论:以EpCAM为标志物的qRT-PCR检测SCLC患者外周血CTCs拷贝数的临床意义有限,仍需继续探索SCLC患者外周血中CTCs捕获的最佳标志物。

Objective:To investigate the application of quantitative fluorescence polymerase chain reaction(qRT-PCR)with epithelial cell adhesion molecule(EpCAM)as a marker to detect circulating tumor cells(CTCs)in small cell lung cancer(SCLC).Methods:A prospective follow-up study was conducted to evaluate the relationship between the number of copies of EpCAM^(+)-CTCs in peripheral blood and clinical characteristics and prognoses of 50 newly treated SCLC patients by qRT-PCR.Results:The number of copies of EpCAM^(+)-CTCs in 50 patients before treatment was between 130.89 to 10971.43 copies/μL.There were no significant differences in the number of EpCAM^(+)-CTCs copies before treatment with clinicopathological features and stage.The number of copies of EpCAM^(+)-CTCs was significantly different from the patient's gender,smoking(P<0.05).The number of EpCAM^(+)-CTCs before and after 2 cycles of treatment and the reduction proportion cannot be used to predict one-year survival.There was no significant difference in the number of EpCAM^(+)-CTCs copies between OS before and after 2 cycles of treatment(P>0.05).Conclusion:qRT-PCR with EpCAM as a biomarker has limit clinical significance in detecting CTCs copy number in patients with small cell lung cancer.It is still necessary to explore better biomarkers to capture CTCs in peripheral blood of SCLC patients.