Diagnostic Potential of Cerebrospinal Fluid Biomarkers in Diagnosis of Primary Central Nervous System Lymphoma: A Systematic Review and Meta-Analysis.

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is an aggressive form of non-Hodgkin's lymphoma primarily restricted to the brain, spinal cord, eyes, and leptomeninges without any evidence of systemic spread. It is often challenging to diagnose PCNSL due to its clinical and radiological overlap with various central nervous system (CNS) inflammatory conditions and other brain tumors. Cytokines and chemokines in cerebrospinal fluid (CSF) have shown potential as biomarkers for PCNSL, but the conclusion on their diagnostic utility is unavailable. This study intended to assess the role of CSF cytokines and chemokines in differentiating PCNSL from other CNS disorders. METHODS: We searched electronic databases extensively to find studies that examined the sensitivity and specificity of CSF cytokine or chemokine levels in PCNSL-synthesizing results involved standardizing the units of measurement where necessary and verifying data accuracy. Pooled effect estimates were computed by meta-analyses utilizing random-effects models. RESULTS: A total of 12 studies were included. The increased levels of CSF interleukin (IL)-10 and C-X-C motif Chemokine Ligant 13 (CXCL 13) were significantly associated with a positive diagnosis of PCNSL. Diagnostic accuracy measures demonstrated the promising discriminatory power of CSF IL-10 and IL-10:IL-6 ratio. CONCLUSION: Our findings revealed considerable diversity in the diagnostic accuracy of individual biomarkers. Notably, CSF IL-10 and CSF IL-10:IL-6 ratios exhibited the highest pooled specificity and sensitivity, suggesting their promising potential as a diagnostic marker for PCNSL.