癌症在世界范围内是一个重大的公共健康问题，有效的早期干预以及疗效监视可以降低肿 瘤患者的发生以及死亡风险。在多数癌症中，外周血循环游离 DNA（Circulating cell⁃free DNA，cfDNA）浓 度及其完整性可能是一类有效的早期诊断、进展期患者识别以及预后监测指标。本文旨在综述 cfDNA 浓 度及其完整性在不同癌症中的诊疗效能，并与当前临床上常用的肿瘤标志物进行对比，探讨该指标在临 床实践中的应用价值以及前景。

Cancer is a major public health problem worldwide，and effective early intervention and effica⁃ cy surveillance can reduce the risk of oncology and death in patients. In most cancers，circulating cell ⁃free DNA （cfDNA）concentration and its integrity may be an effective indicator for early diagnosis，progressive patient identi⁃ fication，and prognostic monitoring. The purpose of this paper is to review the efficacy of cfDNA concentration and its integrity in the diagnosis and treatment of different cancers，and to compare it with the current tumor markers commonly used in clinical practice to explore the value and prospect of this index in clinical practice.