CXCL9 and progressive multifocal leukoencephalopathy: CXCL9 was elevated above the threshold of 84 pg/ml in 12 patients without CNSL: 1 patient with PBT (glioblastoma); 3 patients with SBT from NSCLC (2) and melanoma (1); 4 AID patients (2 multiple sclerosis, 1 neurosarcoidosis, 1 cerebral vasculitis); and 4 NID patients (1 progressive multifocal leukoencephalopathy, 1 cerebral toxoplasmosis, 2 aspergillomas).