Cancer metastasis is the leading cause of cancer-related mortality. The metastatic process involves measurable cellular changes that confer migratory potential, proliferative advantage and the ability to colonise a distinct microenvironment. Accumulation of aberrations and clonal evolution add complexity to patient management and the assessment of the therapeutic sensitivity profile of malignancies. Liquid biopsy presents a repeatable and minimally invasive assessment tool to detect early metastasis, characterise tumour phenotype and detect minimal residual disease. The promise of liquid biopsies is to inform patient management and therapeutic decisions in a timely manner. Clinical translation requires robust methodologies with high sensitivity and tumour specificity. This can be achieved through technological advances but also through novel biologically informed approaches that harness existing knowledge on tumorigenesis. Here we present a review of copy number variations as potential biomarkers for early detection of metastatic potential and outline a biomarker validation process in the context of liquid biopsies.

癌症转移是癌症相关死亡率的主要原因。转移过程涉及可测量的细胞变化，赋予其迁移潜力，增殖优势以及在不同微环境中定殖的能力。畸变的积累和克隆进化增加了患者管理和恶性肿瘤治疗敏感性分布评估的复杂性。液体活检提供了一种可重复且微创的评估工具，可检测早期转移，表征肿瘤表型和检测最小残留疾病。液体活检的承诺是及时告知患者管理和治疗决策。临床翻译需要具有高灵敏度和肿瘤特异性的可靠方法。这可以通过技术进步来实现，也可以通过利用有关肿瘤发生的现有知识的新颖的生物知情方法来实现。在这里，我们介绍了作为潜在的生物标志物的拷贝数变异的回顾，以用于转移性潜能的早期检测，并概述了液体活检背景下的生物标志物验证过程。