Advances in cerebrospinal fluid biomarkers for the diagnosis, treatment and monitoring of leptomeningeal metastases (Review)

Leptomeningeal metastasis (LM) is an aggressive complication characterized by the dissemination of malignant cells to the leptomeninges, typically resulting in rapid neurological deterioration and poor prognosis. Clinical diagnosis and management are impeded by non-specific symptoms and the limited sensitivity of conventional cerebrospinal fluid (CSF) cytology. Consequently, CSF biomarkers have emerged as critical tools for diagnosis, treatment monitoring and prognostic evaluation. The present review summarizes recent advancements in CSF biomarkers, categorizing them into proteins, nucleic acids and metabolites. These biomarkers enhance diagnostic accuracy, facilitate longitudinal disease tracking and assess therapeutic efficacy. Despite notable progress, challenges persist regarding biomarker sensitivity, specificity and standardization. Furthermore, the potential of multi-omics technologies and single-cell analysis is discussed as a pathway for discovering novel biomarkers to enable the precise stratification and personalized management of LM.