摘要胃癌患者的死亡主要源于肿瘤的复发与转移，而循环肿瘤细胞（CTC）是转移的必要条件，作为液体活检具有一定的临床意义。胃癌CTC数量较少，检测需要经过富集，方法包括密度梯度离心法等基于CTC的密度、大小及介电差异等物理特性的方法，以Cell Search System为主的基于免疫源性的方法，以及基于微流控芯片技术的方法。胃癌CTC的检测鉴定多采用免疫荧光法，对分离出来的CTC还可进行核酸水平、蛋白水平及调控水平的后续分析。胃癌CTC的检测有助于临床上判断预后、评估分期、监测疗效及指导药物的研发。尽管胃癌CTC的临床转化也面临富集效率低、特异性表面标记少、以及辅助诊断效率未明等诸多挑战，但相对于病理活检，CTC取材无创，可反复取材、实时监测病情及指导临床治疗，具有良好的研究前景。本文就胃癌CTC的检测鉴定及其临床价值进行介绍。

abstractsThe death of patients with gastric cancer is mainly due to its recurrence and metastasis, and circulating tumor cell (CTC) is the necessary condition of metastasis. As liquid biopsy, CTC detection has its certain clinical significance. The detection is required after enrichment because circulating tumor cells are rare. Many enrichment methods have been developed: methods based on physical characteristics of TCT, like density, size and dielectric properties and so on;immunogenicity, like Cell Search System;and microfluidic chip technology. The immunofluorescence is commonly used to identify CTC in gastric cancer and the isolated CTC can also be used for the following analysis on the level of nucleic acid, protein and gene regulation. Detection of CTC in gastric cancer is helpful to judge the prognosis , assess staging, monitor the curative effect and guide the development of drug. There are many challenges for clinical transformation of CTC: the lower enrichment efficiency, the less specific surface markers, the uncertain diagnostic efficiency and so on, but it also has the good research prospect because it is non-invasive, repeatable and can real-time monitor the condition and guide the clinical treatment compared with pathological biopsy. In this paper, the detection and identification methods, and clinical value of CTC in gastric cancer patients are reviewed.