Transient Leukemia in Down syndrome
Also called:
- Transient Abnormal Hematopoiesis
- Ineffective Regulation of Granulopoiesis
- Transient Congenital Leukemia
- Transient Leukemia-Like Disease
- Transient Abnormal Myelopoiesis
- Transient Leukemia-Like Blood Reaction
- Pseudoleukemia
Overview:
- Only seen in Down Syndrome patients in the newborn period
- Uncontrolled proliferation of myeloblasts, frequently megakaryocytic origin
- Spontaneous resolution typically in first 3 months of life
- Incidence 10-20%
- Presentation:
- Hydrops
- Hepatosplenomegaly
- effusions (pleural, pericardial, peritoneal)
- DIC
- Renal failure
- Respiratory failure
- Lab Features:
- Blood count:
- Elevated white cell count with circulating myeloblasts
- Normal platelets and hemoglobin usually
- Normal neutrophils, basophilia
- Bone Marrow:
- Megakaryoblasts (CD41 and CD61 positive)
- Lower blast percentage in marrow compared to peripheral blood
- Blood count:
- Treatment if:
- Hyperviscosity signs and symptoms
- Blast count >100
- Organomegaly causing respiratory compromise
- Congestive heart failure
- Hydrops fetalis
- Symptomatic hepatic or renal dysfunction
- DIC with bleeding
- Treat with leukapheresis or low dose cytarabine
- Increased risk of AML in patients with history of TMD
AML in Down Syndrome
- Leukemia in children with trisomy 21 mosaicism selectively involves the trisomic cells.
- Trisomy 21 is the first hit in the multistep process leading to leukemia.
- Incidence of leukemia peaks between birth and 4 years of age.
- Develops in 1% of patients with DS.
- 25% of patients with a morphologic diagnosis of RC, RAEB or RAEB-T have Down syndrome.
- Bone marrow blasts <30% in most patients. Bone marrow often fibrotic and difficult to assess.
- AML-M7 subtype often found in patients with Down Syndrome (otherwise rare) and often preceded by MDS.
- Presents often with thrombocytopenia.
- Blast cells have morphologic and antigenic features of megarokaryoblasts.
- Usually responds well to standard therapy for AML (DS children have low risk of relapse but higher risk of therapy induced complications).
Link:
Children with Down Syndrome and leukemia at the National Cancer Institute