循环肿瘤细胞（CTCs）存在于患有癌症的病人血液中，包括头颈鳞状细胞癌（HNSCCs）。目的是回顾CTCs在应用于HNSCC患者中的最新状况。英文PubMed中有关CTCs在HNSCCs中的所有研究均被审查。有关CTCs在HNSCCs中诊断和预测价值的新信息正在涌现。证据还强调了各种下游分析方法在循环肿瘤DNA（ctDNA）之上的优势，如单个CTC分析、体外和体内CTCs扩增。多种表型表面标志物（细胞角蛋白、EpCAM、微丝蛋白等），利用不同的免疫测定方法对CTCs进行表征，可以预测疾病进展以及患者对治疗效果的反应。CTCs中的免疫检查点抑制剂状态也可以提供更好的治疗洞见。CTCs的克隆扩张和单细胞分析是目前最新的领域，可以提供对肿瘤进化机制和治疗效果的理解。尽管许多临床试验正在进行中，但在CTCs的检测和表征方面仍存在一些限制。由于缺乏黄金标准协议，CTC计数方法的灵敏度和特异性都不同。在CTCs可以在HNSCC患者的临床管理中作为诊断和预测标志物之前，还需要进行前瞻性的临床试验。© 2023美国耳鼻喉科-头颈外科基金会。

Circulating tumor cells (CTCs) are found in the blood of patients with cancer, including head and neck squamous cell carcinomas (HNSCCs). The aim is to review the most up-to-date status of CTCs for applications in patients with HNSCC.English articles in PubMed.All the studies on CTCs in HNSCCs in the literature were reviewed.There is emerging information on the diagnostic and prognostic value of CTCs in HNSCCs. Evidence also highlights the advantages of various downstream analysis approaches over circulating tumor DNA (ctDNA), such as single-CTC analysis, ex vivo, and in vivo expansion of CTCs. Multiple phenotypic surface markers (cytokeratins, EpCAM, vimentin, etc.), used for CTCs characterization using different immunoassays, could predict disease progression as well as patients' response to treatment efficacy. Immune checkpoint inhibitors' status in CTCs could also provide better insight into treatment. Clonal expansion of CTCs and single-cell analysis of CTCs are the most emerging fields nowadays which may offer an understanding of the mechanism of tumor evolution as well as therapeutic efficacy. Although several clinical trials are ongoing, limitations still exist in the detection and characterization of CTCs. Due to the lack of a gold standard protocol, the sensitivity and specificity of CTC enumeration methods vary.Prospective clinical trials are still needed before CTCs can be employed as diagnostic and prognostic markers in the clinical management of patients with HNSCC.© 2023 American Academy of Otolaryngology-Head and Neck Surgery Foundation.