Large granular lymphocyte leukemia.
Clonal disorders of large granular lymphocytes (LGLs) represent a spectrum of biologically distinct lymphoproliferative diseases originating either from mature T cells (CD3+) or natural killer (NK) cells (CD3-). Both subtypes, T-cell and NK-cell LGL leukemia, can manifest as indolent or aggressive disorders. The majority of patients with T-cell LGL leukemia have a clinically indolent course with a median survival time >10 years. Immunosuppressive therapy with low-dose methotrexate, cyclophosphamide, or cyclosporine A can control symptoms and cytopenias in more than 50% of patients, but this approach is not curative. Several cases of an aggressive variant (CD3+ CD56+) of T-cell LGL leukemia with a poor prognosis have also been reported. Aggressive NK-cell LGL leukemia is usually a rapidly progressive disorder associated with Epstein-Barr virus (EBV), with a higher prevalence in Asia and South America. This disease is usually refractory to conventional chemotherapy, with a median survival time of 2 months. Chronic NK-cell leukemia/lymphocytosis is a rare EBV-negative disorder with an indolent clinical course. The malignant origin of this subtype is uncertain because clonality is difficult to determine in LGLs of NK-cell origin.
Sokol
Lubomir
L
Department of Interdisciplinary Oncology, University of South Florida and H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA.
Loughran
Thomas P
TP
D000465:Algorithms; D001327:Autoimmune Diseases / Q000209:etiology; D020732:Cytogenetic Analysis; D003937:Diagnosis, Differential; D006402:Hematologic Diseases / Q000209:etiology; D006801:Humans; D015458:Leukemia, T-Cell / Q000175:diagnosis* / Q000209:etiology / Q000235:genetics / Q000628:therapy*; D010641:Phenotype