Tumour molecular profiling by liquid biopsy is being investigated for a wide range of research and clinical purposes. The possibility of repeatedly interrogating the tumour profile using minimally invasive procedures is helping to understand spatial and temporal tumour heterogeneity, and to shed a light on mechanisms of resistance to targeted therapies. Moreover, this approach has been already implemented in clinical practice to address specific decisions regarding patients’ follow‐up and therapeutic management. For central nervous system (CNS) tumours, molecular profiling is particularly relevant for the proper characterization of primary neoplasms, while CNS metastases can significantly diverge from primary disease or extra‐CNS metastases, thus compelling a dedicated assessment. Based on these considerations, effective liquid biopsy tools for CNS tumours are highly warranted and a significant amount of data have been accrued over the last few years. These results have shown that liquid biopsy can provide clinically meaningful information about both primary and metastatic CNS tumours, but specific considerations must be taken into account, for example, when choosing the source of liquid biopsy. Nevertheless, this approach is especially attractive for CNS tumours, as repeated tumour sampling is not feasible. The aim of our review was to thoroughly report the state‐of‐the‐art regarding the opportunities and challenges posed by liquid biopsy in both primary and secondary CNS tumours.

中文翻译：

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通过钥匙孔窥视：原发性和转移性中枢神经系统肿瘤的液体活检

通过液体活检进行的肿瘤分子分析正在被研究用于广泛的研究和临床目的。使用微创手术反复询问肿瘤特征的可能性有助于了解空间和时间的肿瘤异质性，并阐明对靶向治疗的抵抗机制。此外，这种方法已经在临床实践中实施，以解决有关患者随访和治疗管理的具体决定。对于中枢神经系统 (CNS) 肿瘤，分子分析与原发肿瘤的正确表征特别相关，而 CNS 转移可能与原发疾病或 CNS 外转移显着不同，因此需要进行专门的评估。基于这些考虑，用于 CNS 肿瘤的有效液体活检工具是非常必要的，并且在过去几年中积累了大量数据。这些结果表明，液体活检可以提供有关原发性和转移性 CNS 肿瘤的临床上有意义的信息，但必须考虑特定的考虑因素，例如，在选择液体活检来源时。然而，这种方法对 CNS 肿瘤特别有吸引力，因为重复肿瘤取样是不可行的。我们审查的目的是彻底报告有关液体活检在原发性和继发性 CNS 肿瘤中带来的机遇和挑战的最新技术。这些结果表明，液体活检可以提供有关原发性和转移性 CNS 肿瘤的临床上有意义的信息，但必须考虑特定的考虑因素，例如，在选择液体活检来源时。然而，这种方法对 CNS 肿瘤特别有吸引力，因为重复肿瘤取样是不可行的。我们审查的目的是彻底报告有关液体活检在原发性和继发性 CNS 肿瘤中带来的机遇和挑战的最新技术。这些结果表明，液体活检可以提供有关原发性和转移性 CNS 肿瘤的临床上有意义的信息，但必须考虑特定的考虑因素，例如，在选择液体活检来源时。然而，这种方法对 CNS 肿瘤特别有吸引力，因为重复肿瘤取样是不可行的。我们审查的目的是彻底报告关于液体活检在原发性和继发性 CNS 肿瘤中带来的机遇和挑战的最新技术。