Circulating tumor cells (CTCs) are a major contributor of cancer metastases and hold a promising prognostic significance in cancer detection. Performing functional and molecular characterization of CTCs provides an in-depth knowledge about this lethal disease. Researchers are making efforts to design devices and develop assays for enumeration of CTCs with a high capture and detection efficiency from whole blood of cancer patients. The existing and on-going research on CTC isolation methods has revealed cell characteristics which are helpful in cancer monitoring and designing of targeted cancer treatments. In this review paper, a brief summary of existing CTC isolation methods is presented. We also discuss methods of detaching CTC from functionalized surfaces (functional assays/devices) and their further use for ex-vivo culturing that aid in studies regarding molecular properties that encourage metastatic seeding. In the clinical applications section, we discuss a number of cases that CTCs can play a key role for monitoring metastases, drug treatment response, and heterogeneity profiling regarding biomarkers and gene expression studies that bring treatment design further towards personalized medicine.

循环肿瘤细胞（CTC）是癌症转移的主要贡献者，在癌症检测中具有有希望的预后意义。对CTC进行功能和分子表征可提供有关这种致命疾病的深入知识。研究人员正在努力设计设备并开发用于从癌症患者全血中捕获和检测的高效率的CTC枚举的测定方法。有关CTC分离方法的现有研究和正在进行的研究已经揭示了细胞特征，这些特征有助于癌症监测和靶向癌症治疗的设计。在这篇综述文件中，简要介绍了现有的CTC隔离方法。我们还将讨论从功能化表面分离CTC的方法（功能测定/装置）及其在离体培养中的进一步用途，这些方法有助于研究有关鼓励转移性播种的分子特性。在临床应用部分中，我们讨论了许多案例，CTC可以在监测转移，药物治疗反应以及关于生物标志物和基因表达研究的异质性分析方面发挥关键作用，从而使治疗设计进一步朝着个性化医学发展。