Cutaneous non-Hodgkin lymphoma (NHL) which represent a heterogeneous group of T- and B-cell lymphomas.
- #2 M/C extranodal manifestation of NHL (M/C: GIT)
Classification
WHO-EORTC classification:
- Cutaneous T-cell lymphomas (CTCL) (> 65%)
- Cutaneous B-cell lymphomas (CBCL) (25%)
- Unspecific (10%)
CTCL subtypes:
- Indolent CTCL subtypes:
- Mycosis fungoides (MF) (M/C)
- Other variants: Anaplastic large T-cell PCL, lymphomatoid papulosis, subcutaneous panniculitis-like T-cell lymphomas with alpha/beta T-cell phenotype, cutaneous lymphomas of T CD4+ cells of small and medium-sized pleomorphic cells
- Aggressive subtypes:
- Sézary Syndrome (SS)
- Others: PCL such as nasal-type T/NK-cell, T CD4- and CD8+ cells, unspecific T-cell and the T cell lymphoma/leukaemia of adults

Aetiology
- Human T-cell lymphotropic virus type 1 (HTLV-1) (associated with Adult T cell leukaemia/lymphoma)