Additionally, there were two false positive cases of GBM and brain involvement of Sjögren's syndrome in the 4‐marker (CXCL13, IL‐10, β2‐MG, and sIL‐2R) and 3‐marker (CXCL13, IL‐10, and β2‐MG) algorithms. This evidence concerns the gene CXCL13 and Sjogren syndrome.