Molecular classification of the peripheral T-cell lymphomas

Molecular classification of peripheral T-cell Lymphomas (PTCLs) provides vital information about the maturation, activation state, and molecular pathogenesis of PTCL entities. To understand the development of PTCL, it is essential to trace T-cell development, which briefly describes T-lymphocyte generation and activation. Non-Hodgkin lymphomas (NHL) derived from the T and natural killer (NK) cell lineage represent a highly heterogeneous subset of malignancies with varied morphological and clinical features. They typically comprise about 15-20% of all NHLs in the Western world. The World Health Organization currently recognizes at least 29 entities with angioimmunoblastic T-cell lymphoma, anaplastic large-cell lymphoma, adult T-cell leukemia/lymphoma, extranodal NK/T-cell lymphoma, nasal type, and PTCL-NOS, representing approximately 80% of all diagnoses. Molecular classifications can be adapted from gene expression signatures into modalities more suited for future clinical use.