Clinical significance of interleukin-10 concentration in the cerebrospinal fluid of patients with primary central nervous system lymphoma

The diagnostic and prognostic evaluation of primary central nervous system lymphoma (PCNSL) is challenging due to the lack of sensitive biomarkers. The present study aimed to evaluate the value of interleukin (IL)-10 in this context. Between October 2016 and December 2018, 91 patients with suspected intracranial neoplasms were recruited, and the concentrations of IL-10 or IL-6 in both the cerebrospinal fluid (CSF) and blood were measured and analyzed by the Kruskal-Wallis test. The correlation between CSF IL-6 or IL-10 levels and tumor size was determined by Spearman's coefficient analysis. The receiver operating characteristic curve was used to evaluate the diagnostic value of CSF IL-6 and IL-10 levels. Median progression-free survival (PFS) and overall survival time were calculated using Kaplan-Meier survival analysis. Among the 91 patients, 3 were diagnosed with PCNSL on the basis of neuroimaging data and CSF IL-10 levels. A total of 35 cases were verified to show diffuse large B-cell lymphoma on histological assessment, 17 of which were diagnosed as PCNSL by MRI. The median PFS and OS were 8.00 months [95% confidence interval (CI), 3.94–12.06) and 17.5 months (95% CI, 11.55–23.45) respectively in the 12 PNCSL cases with regular follow up. The diagnostic efficiency of serum IL-6 levels was lower than that of serum IL-10 levels (P=0.030), which, in turn, was lower than that of CSF IL-10 levels (P<0.001). The decline and increase in CSF IL-10 levels was concurrent with improvement and deterioration in manifestation, respectively, which predated the MRI variation. High CSF IL-10 levels indicated low Karnofsky performance scale scores and shortened PFS times. CSF IL-10 levels higher than 1,000 pg/ml signified disease progression. CSF IL-10 levels could be a sensitive biomarker guiding the differential diagnosis, early recurrence detection, prognostic evaluation and therapeutic strategy establishment in cases of PCNSL.