Genetics Abnormalities with Clinical Impact in Primary Cutaneous Lymphomas

Area of Science:

• Oncology
• Genetics
• Dermatology

Background:

• Primary cutaneous lymphomas are extranodal non-Hodgkin lymphomas originating in the skin.
• They are broadly classified into T-cell (70%), B-cell (25-30%), and rare NK-cell types.
• Cutaneous T-cell lymphomas (CTCL) include Mycosis Fungoides (MF) and Sézary syndrome (SS).

Purpose of the Study:

• To investigate the genetic landscape of various primary cutaneous lymphomas.
• To identify key genomic alterations for diagnostic and prognostic purposes.
• To highlight the need for pathway-based personalized management in CTCL.

Main Methods:

• Next-generation sequencing (NGS) to analyze the mutational landscape of MF and SS.
• Analysis of genomic copy number variations.
• Genetic profiling of other CTCL subtypes and cutaneous B-cell lymphomas (CBCL).

Main Results:

• MF and SS show recurrent genomic alterations in TCR signaling, NF-κB, DNA damage/repair, JAK/STAT pathways, and epigenetic modifiers.
• Genomic copy number variations are more prevalent than somatic mutations in CTCL.
• Specific genetic alterations, such as JAK2 rearrangements in aggressive epidermotropic T-cell lymphoma and MYD88 mutations in leg-type diffuse large B-cell lymphoma, are identified.

Conclusions:

• CTCL patients possess a heterogeneous genetic, transcriptional, and epigenetic background, necessitating personalized treatment approaches.
• Genetic profiles of CBCL subtypes vary, with specific mutations aiding in the diagnosis and prognosis of aggressive forms like leg-type diffuse large B-cell lymphoma.
• Understanding the distinct genetic alterations in primary cutaneous lymphomas is essential for targeted therapies and improved patient outcomes.