PTCL-NOS
Peripheral T-cell lymphoma not otherwise specified
Medical condition
Peripheral T-cell lymphoma not otherwise specified (PTCL-NOS), is a subtype of peripheral T-cell lymphoma. Peripheral T-cell lymphoma (PTCL) is defined as a diverse group of aggressive lymphomas that develop from mature-stage white blood cells called T-cells and natural killer cells (NK cells) (see figure for an overview of PTCL subtypes). PTCL is a type of non-Hodgkin's lymphoma (NHL).[2] PTCL specifically affects T-cells rather than B-cells, and results when T-cells develop and grow abnormally.
About 30% of PTCL-NOS cases exhibit malignant T cells that are infected with the Epstein-Barr virus (EBV). When associated with EBV, PTCL-NOS is classified as one of the Epstein-Barr virus-associated lymphoproliferative diseases (see Epstein-Barr virus-associated peripheral T cell lymphoma, not otherwise specified) but the relationship of EBV to the development and progression of Epstein-Barr virus-associated PTCL-NOS is unclear.[3]
PTCL-NOS, the most common subtype of PTCL, is aggressive and predominantly nodal. There are two morphologic variants: the T-zone lymphoma variant and the lymphoepithelioid cell variant.[4][5]
- T-zone lymphoma is so named for its involvement in a specific area of the lymph node that consists of a dense accumulation of T-cells.[6]
- Lympho-epithelioid lymphoma, also called Lennert's lymphoma, is rare and generally affects older individuals.[7]