Targeted panel sequencing for refining B-cell lymphoma diagnosis: a real-life, reference center experience

Area of Science:

• Hematology
• Oncology
• Molecular Diagnostics

Background:

• Accurate B-cell lymphoma (BCL) diagnosis relies on integrated approaches including morphology, immunophenotyping, and clinical data.
• The mutational landscape of BCL is increasingly recognized as a valuable diagnostic adjunct.
• Distinguishing between subtypes like Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) can be challenging.

Purpose of the Study:

• To develop and validate a custom next-generation sequencing (NGS) panel for routine BCL diagnosis.
• To assess the utility of NGS panel sequencing in supporting BCL diagnosis and differential diagnosis (DD).
• To evaluate the impact of NGS in challenging cases, particularly differentiating BL from DLBCL.

Main Methods:

• Development of a custom NGS panel based on literature review and diagnostic needs.
• Application of the NGS panel to 160 routine cases of BCL or with differential diagnoses.
• Analysis of diagnostic yield and decision-making impact, with a focus on 21 challenging BL/DLBCL cases.

Main Results:

• Evaluable results were obtained in 99% (158/160) of cases.
• Diagnostically informative molecular profiles were identified in 72% of evaluable cases.
• In 21 challenging BL/DLBCL cases, NGS detected mutations in all cases, providing significant guidance in 86% (18/21).

Conclusions:

• NGS panel sequencing offers substantial diagnostic assistance in BCL, complementing traditional methods like morphology and immunohistochemistry.
• The custom NGS panel is particularly valuable for clarifying difficult differential diagnoses, such as BL versus DLBCL.
• Molecular profiling via NGS enhances diagnostic accuracy and supports clinical decision-making in BCL.