Chronic liver diseases account for a considerable toll of incapacities, suffering, deaths, and resources of the nation's health systems. They can be prevented, treated or even cured when the diagnosis is made on time. Traditional liver biopsy remains the gold standard to diagnose liver diseases, but it has several limitations. Liquid biopsy is emerging as a superior alternative to surgical biopsy given that it surpasses the limitations: it is more convenient, readily and repeatedly accessible, safe, cheap, and provides a more detailed molecular and cellular representation of the individual patient's disease. Progress in understanding the molecular and cellular bases of diseased tissues and organs that normally release cells and cellular components into the bloodstream is catapulting liquid biopsy as a source of biomarkers for diagnosis, prognosis, and prediction of therapeutic response, thus supporting the realization of the promises of precision medicine. The review aims to summarize the evidence of the usefulness of liquid biopsy in liver diseases, including the presence of different biomarkers as circulating epithelial cells, cell-free nucleic acids, specific species of DNA and RNA, and the content of extracellular vesicles.

慢性肝病在国家卫生系统的丧失能力、痛苦、死亡和资源方面造成了相当大的损失。如果及时做出诊断，它们可以被预防、治疗甚至治愈。传统的肝活检仍然是诊断肝脏疾病的金标准，但它有几个局限性。液体活检正在成为手术活检的优越替代方案，因为它超越了局限性：它更方便、更容易和可重复访问、安全、便宜，并提供了个体患者疾病的更详细的分子和细胞表征。在了解正常将细胞和细胞成分释放到血液中的患病组织和器官的分子和细胞基础方面取得的进展正在将液体活检作为诊断生物标志物的来源，预后和治疗反应的预测，从而支持实现精准医疗的承诺。该综述旨在总结液体活检在肝脏疾病中有用的证据，包括不同生物标志物的存在，如循环上皮细胞、无细胞核酸、特定种类的 DNA 和 RNA，以及细胞外囊泡的含量。