MedGen

Acute lymphoblastic leukemia of T-cell origin. It comprises about 15% of childhood cases and 25% of adult cases. It is more common in males than females. [from HPO]

A rare acute lymphoblastic leukemia characterized by a neoplasm of lymphoblasts committed to the T-cell lineage, involving bone marrow and blood. A value of >25% bone marrow blasts may be used to define leukemia (as opposed to lymphoma) in cases with the presence of a mass lesion in addition to bone marrow involvement. Patients typically present with leukocytosis, and frequently with a large mediastinal or other tissue mass. Lymphadenopathy and hepatosplenomegaly are common. [from ORDO]

A rare, virus associated tumor due to human T-cell leukemia virus type 1 or human T-cell lymphotropic virus type 1 (HTLV-1) and is characterized by the presence of anti-HTLV-1 antibodies, and malignant, mature, medium-sized T cells with condensed chromatin and polylobated nuclei. The malignant cells exhibit a mature CD4+ T cells phenotype and express CD2, CD5, CD25, CD45RO, HLA-DR, and T-cell receptor αβ. Presentation is heterogeneous and is typically of aggressive leukemia or lymphoma, variable skin eruptions, and visceral organ involvement. [from ORDO]

A malignant disease of the T-lymphocytes in the bone marrow, thymus, and/or blood. [from MONDO]