The following is a summary of “Mutational heterogeneity in large B-cell lymphoma: insights from paired biopsies,” published in the December 2024 issue of Hematology by Hersby et al.
Large B-cell lymphoma (LBCL) shows significant clinical and molecular heterogeneity. New methods are needed to fully capture its complexity, raising questions about the adequacy of single-site biopsies.
Researchers conducted a retrospective study to explore spatial and temporal mutational variations in LBCL using paired biopsies.
They obtained paired biopsies from 30 patients with LBCL, collected from distinct sites at primary diagnosis and/or relapse. The samples were sequenced using a 59-gene next-generation sequencing (NGS) lymphoma panel.
The results showed frequent differences in pathogenic mutations, with 2/6 (33%) in paired diagnostic biopsies and 8/16 (50%) in paired biopsies at diagnosis and relapse. Mutational heterogeneity increased with longer time intervals between biopsies. Analysis revealed that clones present at diagnosis disappeared at relapse, while new clones emerged. TP53 mutations were found in 6/7 patients at extranodal sites, with 2 cases showing mutations only in relapse biopsies. Several mutations identified are being explored as cancer treatment targets.
They found significant spatial and temporal mutational heterogeneity in LBCL, with differences between biopsy pairs at all timepoints. This highlighted the need for repeat biopsies at relapse to fully capture genetic variations.
Source: link.springer.com/article/10.1007/s00277-024-06108-w
