The MYD88 alteration has been found at high frequencies in cutaneous DLBCL (69%), primary testicular lymphoma (68%), primary central nervous system lymphoma (38–86%), or ABC DLBCL (30%), indicating its role in the pathogenesis of lymphoid neoplasia [23,35,36,37,38,39]. The gene discussed is MYD88; the disease is primary central nervous system lymphoma.