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Precursor T-cell acute lymphoblastic leukemia

Disease definition

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.


Classification level: Disorder
  • Synonym(s):
    • Precursor T-cell acute lymphoblastic leukemia/lymphoma
    • Precursor T-cell acute lymphocytic leukemia
    • Precursor T-cell acute lymphocytic leukemia/lymphoma
    • T-ALL
  • Prevalence: -
  • Inheritance: Not applicable 
  • Age of onset: Adult, Adolescent
  • ICD-10: C91.0
  • OMIM: -
  • UMLS: C1961099
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information


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