Integration of mutational data with PMBCL/DLBCL gene expression signatures. For 37 of the 42 group 1-2 GZLs in this cohort and 14 PMBCLs, RNA sequencing data have been reported previously.¹⁰  For each sample (columns), the heat map shows expression (normalized and log-transformed counts) of genes (rows) comprising the Lymph3Cx³⁸  gene signature that distinguishes PMBCL from DLBCL (with PMBCL genes in light purple and DLBCL genes in dark purple). DLBCL-related genes and PMBCL-related genes formed 2 uniform clusters according to tumor cell expression patterns. For the mutation track, genes were selected based on their enrichment in thymic GZL (LRRN3, NFKBIE, TNFAIP3, GNA13, B2M) and nonthymic GZL (CREBBP, TP53, BCL2). Filled boxes (dark gray or blue) represent cases with mutations present, and light gray boxes represent no mutation.