Clinical utility of real-time comprehensive molecular testing in large B-cell lymphoma

Due to the rapidly evolving landscape of targeted therapies, there is an unmet need for comprehensive molecular profiling to guide treatment decisions for patients with large B-cell lymphoma (LBCL). Therefore, we designed a pilot study to assess the feasibility and turnaround time (TAT) of a comprehensive whole exome sequencing (WES) and transcriptome sequencing (RNA-seq) assay in patients with LBCL (NCT05464823). Patients aged ≥18 years with LBCL were eligible. Formalin-fixed paraffin-embedded tissues at diagnosis or recurrence underwent WES, RNA-seq, and copy number analysis with concomitant germline DNA sequencing. Genomic and transcriptomic data were profiled to define various LBCL signatures such as cell-of-origin (COO), dark zone signature (DZsig), LymphGen and lymphoma microenvironment (LME) classification. Among 100 patients enrolled, samples from 71 patients (48 with newly diagnosed and 23 with relapsed/refractory disease) passed pathology quality control and underwent WES and RNA-seq analysis and reporting. The median TAT was 8 days for individual patient reports (range: 6-22 days), with 73% of reports delivered ≤10 days. Applying molecular risk classification, high risk event-free survival within 24 months (EFS24) signature was associated with DZsig and LME, but not with COO or LymphGen indicating the complex heterogeneity of the disease. We demonstrated the clinical utility and acceptable TAT of a comprehensive WES and RNA-seq assay for LBCL managed in routine clinical practice. These findings support the real-world feasibility of using integrated WES and RNA-seq to define molecular subgroups, guide clinical decision-making at the time of a new line of therapy, and enable biology based subtype-driven clinical trials.