Somatic copy number aberrations in prDLBCL compared with other subtypes of DLBCL including IP-LBCL. (A) Genome-wide frequency of somatic copy number amplifications (red) and deletions (blue) across all chromosomes in prDLBCL. Key regions with recurrent alterations are annotated, including PRDM1, CDKN2A, HLA-B, and NFKBIZ, highlighting their potential involvement in lymphomagenesis and immune evasion. The x-axis represents chromosomal locations, whereas the y-axis indicates the frequency of alterations across the cohort. (B) Amplifications and deletions at recurrently affected loci in an all-comer cohort of DLBCL (first column), DLBCL of ABC and GCB subtypes (second and third column), and IP-LBCL with primary CNS or primary testicular manifestation (columns 4 and 5) compared to prDLBCL (column 6). (C) Impairment of the MHC class I and II apparatus as well as its immediate interaction partners by mutations and/or SCNAs. PTLBL, primary testicular large B-cell lymphoma; SCNA, somatic copy number aberration.