Of note, several genes reflecting B cells (CD20/MS4A1, CD19, CD22, CD79B) were significantly highly expressed in HLA‐I+ compared to HLA‐I− lymphomas (Supporting Information S1: Table 2), suggesting that the prognostically favorable B‐cell‐rich TME is a feature of HLA‐I+ HL. This evidence concerns the gene MS4A1 and lymphoma.