Identification of groups of tumors with coordinate genetic signatures in patients with rrDLBCL. (A) A heat map showing individual mutations in 105 patient samples color coded by mutation type. The top plot shows the absolute number of oncogenic mutations in each patient. The graph on the right shows the number of mutations in each gene. Percentages represent the fraction of tumors with at least 1 mutation in the specified gene. Fifty recurrently and significantly mutated genes are sorted according to their mutational frequencies. Genes with a mutation frequency >5% are shown. (B) Nonnegative matrix factorization consensus clustering was performed on mutated genes in the 105 DLBCL samples. Clusters with their associated landmark genetic alterations are shown. Distinct clusters are identified by color. Genetic alterations that were positively associated with each cluster were identified by 1-sided Fisher's exact test and ranked by frequency. P < .05, right.