Next-Generation Sequencing-Based T-Cell Receptor Gene Rearrangement Analysis in Nodal T Follicular Helper Cell...

Area of Science:

• Hematology
• Oncology
• Molecular Biology

Background:

• Nodal T follicular helper cell lymphoma (nTFHL) presents diagnostic challenges due to immune dysregulation features and low neoplastic T cell counts.
• Accurate diagnosis is crucial for effective treatment and patient outcomes.

Purpose of the Study:

• To compare the diagnostic performance of next-generation sequencing (NGS) with conventional EuroClonality/BIOMED-2 assays for T-cell receptor (TR) gene rearrangements in nTFHL.
• To evaluate the ability of NGS to detect small or multiple clones characteristic of nTFHL.

Main Methods:

• DNA extraction from 32 formalin-fixed, paraffin-embedded nTFHL samples.
• NGS amplicon-based analysis of TRBV-TRBD-TRBJ, TRBD-TRBJ, and TRGV-TRGJ rearrangements.
• Conventional EuroClonality/BIOMED-2 clonality assays.

Main Results:

• Both NGS and conventional assays showed high clonality detection rates (97% and 94%, respectively).
• NGS identified two or more clonal targets in all positive cases, while the conventional assay missed some in three cases.
• NGS provided comprehensive data on clone abundance, sequences, clonotypes, and productivity.

Conclusions:

• NGS provides more reliable detection of T-cell receptor rearrangements, including small clones crucial for nTFHL diagnosis.
• NGS-based TR rearrangement analysis offers a more detailed molecular profile, suggesting a need for updated interpretation guidelines.