CXCL13 levels were elevated above the predetermined cut-off of 80 pg/ml in 10 patients without CNSL: 2 patients with PBT (glioblastoma); 5 patients with SBT and concomitant meningeosis carcinomatosa deriving from breast (3) and non-small cell lung cancer (NSCLC) (2); 2 AID patients (multiple sclerosis); and 1 NID patient (septic emboli from bacterial endocarditis and concomitant meningitis). This evidence concerns the gene CXCL13 and multiple sclerosis.