PCNSL harbor BCR-activating mutations in CD79B and TLR-activating mutations in MYD88 at a higher frequency than systemic ABC type DLBCL, whereas oncogenic mutations in CARD11 and TNFAIP3 occur less frequently in PCNSL [20,21,22,23,24]. Here, TNFAIP3 is linked to primary central nervous system lymphoma.