High frequency of mutated CD37 in IP-DLBCL. (A) Frequency of CD37 mutations in non-IP-DLBCL vs IP-DLBCL. The total number of lymphoma cases for each group is indicated. Numbers in the CD37 mutation row indicate the number of lymphoma cases carrying ≥1 CD37 mutation. P values were obtained using the Fisher’s exact test. (B) OncoPrint (left) and Venn diagram (right) show the frequencies of CD37, CARD11, CD79A, CD79B, and MYD88 mutations in all IP-DLBCL cases studied (23 PTL and 21 PCSNL). Columns show individual tumors. Asterisk indicates samples from the same patient containing the CD37 germline mutation. Genetic details per mutation can be found in supplemental Table 2. Green, missense mutation; black, splice-site mutation; magenta, deletion; gray, no mutation. (C) Schematic representation of mutations detected in the CD37 gene. Dark gray boxes represent the coding sequence of CD37, light gray boxes are the noncoding sequence before exon 1 (begin) and after exon 8 (end), and black lines represent introns. Asterisk indicates the CD37 germline mutation.