Molecular landscape of high-grade B-cell lymphoma in children

Aggressive B-cell non-Hodgkin lymphomas in children, adolescents, and young adults (CAYA) include diffuse large B-cell lymphoma (DLBCL), the genetically well-defined Burkitt lymphoma (BL), and the recently recognised large B-cell lymphoma/high-grade lymphoma with 11q-aberration (LBCL/HG-11q). However, a subset of morphologically high-grade B-cell lymphomas (HGBCL) do not fulfil criteria to be included in these categories and their genetic profile has not been completely elucidated. Using an integrated approach, including fluorescence in situ hybridization, targeted gene Next Generation Sequencing (NGS) for the identification of 11 structural variants and 168 mutations characteristic of B-cell lymphoma, copy number arrays, and gene expression profiling (DLBCL90), we characterized 37 B-cell lymphomas in CAYA with intermediate features between DLBCL and BL. Overall, the genetic profile of aggressive B-cell NHL in CAYA in the spectrum of BL and DLBCL is heterogeneous. MYC-R cases mostly displayed a molecular profile close to BL regardless of their morphology, whereas MYC-non-R had a more heterogeneous genetic landscape resembling DLBCL.