作者：陈晓霞1，陈伟2，林灿祥3，刘奕龙1，曹素梅1

单位：1.中山大学肿瘤防治中心 肿瘤预防研究室，广东 广州 510060； 2.中山大学附属第一医院 胃肠外科，广东 广州 510080； 3.中山大学附属孙逸仙纪念医院 心胸外科，广东 广州 510120

Authors:  Chen Xiaoxia1, Chen Wei2, Lin Canxiang3, Liu Yilong1, Cao Sumei1

Unit:  1.Department of Epidemiology, Cancer Prevention Center, Sun Yat-sen University Cancer Center, Guangzhou 510060, Guangdong, China； 2.Department of Gastrointestinal Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, Guangdong, China； 3.Department of Cardiothoracic Surgery in Sun Yat-Sen Memorial Hospital, SunYat-Sen University, Guangzhou 510120, Guangdong, China

摘要：

肿瘤早期诊断是有效提高肿瘤预后的最重要手段之一。目前临床上主要采用影像、内镜、肿瘤标志物等对肿瘤进行早期筛查,然而其发现早期肿瘤的敏感性仍不够理想。液体活检(Liquid biopsy)是通过采集能代表患者发病部位的体液(如血液、唾液、汗液、粪便、尿液及分泌物等),对体内的肿瘤或其他生理状态进行监测的一种新兴体外诊断技术。目前常见的检测项目包括循环肿瘤细胞(Circulating tumor cell, CTCs)、循环肿瘤DNA(Circulating tumor DNA, ctDNA)及肿瘤细胞来源的外泌体(tumor cell-drived exo-somes, TEXs)等。液体活检采用高通量测序、PCR等手段,对检出极微量的肿瘤来源核酸等标志物具有很高的敏感性,因此可以用于肿瘤的早期乃至超早期筛查。大多数液体活检的对象是血液样品,容易实现对多种肿瘤的同步覆盖,从而大大提高早筛效率并降低成本。同时,液体活检具有无创、可重复性强、样本获取方便等优点。因此,液体活检有望提高无症状高危人群的肿瘤早期检出率,帮助临床医生把握肿瘤的最佳治疗时机,有效地提高患者的生存率。

关键词：  液体活检; 肿瘤标记物; 早期筛查; CTCs; ctDNA; 外泌体; 高通量测序; PCR

Abstract：

Early diagnosis for tumor is one of the most important methods to improve the prognosis of cancer. At present, imaging, endoscopy and tumor markers are mainly used for early screening of tumors. However, the sensitivity of early detection of tumors is still not optimal. Liquid biopsies is a new technique for tumor in vitro diagnosis or other physiological status by collected humours (such as blood, saliva, sweat, feces, urine and secretions), which can represent the location of the disease. At present, the common detection items include circulating tumor cell (CTCs), circulating tumor DNA (ctDNA) and tumor cell-derived exocrine (TEXs). Liquid biopsy is highly sensitive to the detection of very small amounts of tumor-derived nucleic acids and other markers by high-throughput sequencing and polymerase chain reaction (PCR), therefore, it can be used for early and ultra-early screening of tumors. Most liquid biopsies are blood samples, which are easy to achieve simultaneous coverage of multiple tumors, thus greatly improving the efficiency of early screening and being cost effective. At the same time, liquid biopsy has the advantages of non-invasive, reproducible and easy to obtain samples. Therefore, liquid biopsy is expected to improve the early detection rate of tumors in asymptomatic high-risk population, help clinicians to grasp the optimal time for treatment of tumors, and effectively improve the survival rate of patients in tumor treatment.

Key Words:  Liquid biopsy; Tumor markers; Early screening; CTCs; ctDNA; Exosome; High-throughput sequencing; PCR