KEY TAKEAWAYS
- The study aimed to investigate the distinctive features of PB-DLBCL, focusing on its clinical presentation, morphology, phenotype, GEP, and molecular genetics for better characterization.
- Researchers noticed that the comprehensive characterization of PB-DLBCL provides valuable insights for tailored therapeutic strategies and enhances understanding of its pathogenesis.
Primary Bone Diffuse Large B-cell Lymphoma (PB-DLBCL) lacks recognition as a distinct entity in current classification systems. Vanesa-Sindi Ivanova and her team aimed to define and B-cell Lymphoma highlight its unique clinical presentation, morphology, phenotype, gene expression profile (GEP), and molecular genetics.
Researchers performed an inclusive analysis involving 27 respective cases of PB-DLBCL. The investigation encompassed phenotype examination, gDNA panel sequencing of 172 genes, and fluorescence in situ hybridization for MYC, BCL2, and BCL6 translocations. Cases were genetically subclassified using the Two-step classifier, and cell-of-origin subtyping was conducted through GEP. In silico comparison revealed up- and downregulated genes specific to PB-DLBCL compared to other DLBCL subtypes.
About 22 cases in the study demonstrated a germinal center B-cell-like (GCB) phenotype by immunohistochemistry and all by GEP. The mutational profile of PB-DLBCL closely resembled that of follicular lymphoma and nodal GCB-DLBCL, exhibiting more frequent TP53 and B2M mutations. In PB-DLBCL, the unique GEP revealed a lower frequency of BCL2 rearrangements compared to nodal GCB-DLBCL. The Two-step classifier categorized eight cases as EZB, three as ST2, and one as MCD.
The study concluded that the comprehensive characterization of PB-DLBCL as a distinct entity with unique clinical and morpho-molecular features provides valuable insights for developing tailored therapeutic strategies and enhances understanding of its pathogenesis.
The study is sponsored by Swiss Cancer Research Foundation & Swiss Cancer League
Source: https://pubmed.ncbi.nlm.nih.gov/37965677/
Ivanova VS, Davies J, Menter T, et.al. Primary bone diffuse large B-cell lymphoma (PB-DLBC): a distinct extranodal lymphoma of germinal centre origin, with a common EZB-like mutational profile and good prognosis. Histopathology. 2024 Feb;84(3):525-538. doi: 10.1111/his.15096. Epub 2023 Nov 15. PMID: 37965677.