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Start free with EleplanPrecursor T-cell acute lymphoblastic leukemia
ORPHA:99861Disease
Also called Precursor T-cell acute lymphoblastic leukemia/lymphoma · Precursor T-cell acute lymphocytic leukemia · Precursor T-cell acute lymphocytic leukemia/lymphoma · T-ALL
What it is
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.
Key facts
- Age of onset
- Adolescent, Adult
- Inheritance
- Not applicable
- Classified as
- Disease
Recorded for the broader condition
- Prevalence
- 1-5 / 10 000 (Europe)Acute lymphoblastic leukemia
Orphanet records these for the broader condition rather than for this specific form. They are a starting point, not a figure for this subtype — subtypes often differ, and some are defined by being rarer than the condition they sit under.
Genes
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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