Molecular Dx Significance 7/10

Pathogenesis of T-Cell Lymphomas Revealed by NGS and Gene Expression Profiling

NGS and transcriptomic studies have identified subtype-specific genetic signatures across T-cell lymphomas, with RHOA and TET2 mutations prevalent in nodal subtypes and JAK-STAT pathway activation enriched in extranodal forms such as NK/T-cell and hepatosplenic lymphomas. Epigenetic modifier mutations are implicated across all subtypes but with distinct patterns. These findings are refining diagnostic criteria, improving prognostication, and identifying actionable therapeutic targets.

The original study

Novel insights into the pathogenesis of T-cell lymphomas.

Authors
Van Arnam JS, Lim MS, Elenitoba-Johnson KSJ
Journal
Blood
Type
Journal Article, Review
PMID
29666117
Read the original study →

Original abstract

T-cell lymphomas are a heterogeneous group of rare malignancies with overlapping clinical, immunologic, and histologic features. Recent advances in our understanding of T-cell differentiation based on gene expression profiling, next-generation sequencing, and transgenic mouse modeling studies have better elucidated the pathogenetic mechanisms underlying the diverse biology of T-cell lymphomas. These studies show that although genetic alterations in epigenetic modifiers are implicated in all subtypes of T-cell lymphomas, specific subtypes demonstrate enrichment for particular recurrent alterations targeting specific genes. In this regard, RHOA and TET2 alterations are prevalent in nodal T-cell lymphomas, particularly angioimmunoblastic T-cell lymphomas, peripheral T-cell lymphomas (PTCLs) not otherwise specified, and nodal PTCLs with T-follicular helper phenotype. JAK-STAT signaling pathways are mutationally activated in many extranodal T-cell lymphomas, such as natural killer/T-cell and hepatosplenic T-cell lymphomas. The functional significance of many of these genetic alterations is becoming better understood. Altogether these advances will continue to refine diagnostic criteria, improve prognostication, and identify novel therapeutic targets, resulting in improved outcomes for patient with T-cell lymphomas.