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Start free with EleplanPrecursor B-cell acute lymphoblastic leukemia
ORPHA:99860Disease
Also called B-ALL · Precursor B-cell acute lymphoblastic leukemia/lymphoma · Precursor B-cell acute lymphocytic leukemia · Precursor B-cell acute lymphocytic leukemia/lymphoma
What it is
A rare acute lymphoblastic leukemia characterized by infiltration of bone marrow and peripheral blood by small to medium-sized blast cells typically positive for the B-cell markers CD19, cCD79a, and cCD22. Predilection sites for extramedullary involvement are the central nervous system, lymph nodes, spleen, liver, and testes. Patients present with evidence of bone marrow failure (i. e. thrombocytopenia, anemia, and/or neutropenia) and variable leukocyte count, as well as lymphadenopathy, hepatomegaly, splenomegaly, bone pain, and arthralgias.
Key facts
- Age of onset
- Childhood
- 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 reported in subtypes
Orphanet records these genes on 8 more specific entries under this disorder, not on this entry itself:
A well-studied disease is usually split into subtypes, and the gene is curated on whichever one the evidence belongs to. Open a subtype to see which gene goes with it.
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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