Lymphoma, Extranodal NK-T-Cell

**Definition:** An extranodal neoplasm, usually possessing an NK-cell phenotype and associated with EPSTEIN-BARR VIRUS. These lymphomas exhibit a broad morphologic spectrum, frequent necrosis, angioinvasion, and most commonly present in the midfacial region, but also in other extranodal sites.

**Tree numbers:** - C04.557.386.480.750.199

**Synonyms:** - Extranodal NK-T-Cell Lymphoma