Approach to nodal-based T-cell lymphomas.

Area of Science:

• Hematology
• Oncology
• Pathology

Background:

• Peripheral T-cell lymphomas (PTCLs) are uncommon, aggressive T-cell malignancies with variable presentation.
• The majority of PTCLs present as nodal diseases.
• Recent classifications incorporate molecular data, refining PTCL definitions but posing diagnostic challenges.

Purpose of the Study:

• To provide an updated summary of clinicopathological and molecular features of common nodal PTCLs.
• To offer practical recommendations for diagnosing nodal T-cell lymphoproliferations.
• To discuss diagnostic challenges, mimics, and criteria for identifying distinct PTCL entities.

Main Methods:

• Review of clinicopathological and molecular features of common nodal PTCLs.
• Synthesis of recent molecular genetic data from gene expression profiling and next-generation sequencing.
• Analysis of diagnostic challenges and differential diagnosis with reactive conditions.

Main Results:

• Nodal PTCLs are heterogeneous, including angioimmunoblastic T-cell lymphoma, follicular T-helper cell-derived lymphomas, anaplastic large cell lymphomas, and PTCL-not otherwise specified.
• Distinguishing PTCLs from reactive conditions and subtypes remains challenging despite classification updates.
• Ancillary studies are crucial for accurate diagnosis and subtype identification.

Conclusions:

• Accurate diagnosis of PTCL subtypes requires integrating clinicopathological, molecular, and ancillary study findings.
• Understanding diagnostic pitfalls and mimics is essential for correct PTCL identification.
• This review provides a framework for improved diagnostic approaches to nodal T-cell lymphoproliferations.