Mast cell leukaemia is an extremely aggressive subtype of acute myeloid leukaemia that usually occurs de novo but can, rarely, evolve from transformation of chronic myeloid leukaemia into the more aggressive acute myeloid leukaemia.
WHO criteria
- Prevalence of 20% neoplastic mast cells in marrow and 10% in blood.
- “Aleukemic” mast cell leukaemia: Mast cells represent < 10% of blood cells
Clinical features
Rapidly progressive disorder with leukemic mast cells in blood and in large numbers in marrow.
- Common signs and symptoms:
- Fever, headache, flushing of face and trunk
- Typical cutaneous mast cell infiltrates of urticaria pigmentosa are usually not present before, during, or after diagnosis in patients who have mast cell leukemia.
- Histamine release from neoplastic mast cells:
- Abdominal pain, bone pain, and peptic ulcer
- More prevalent than in other subtypes of AML
- Abdominal pain, bone pain, and peptic ulcer
- Hepatosplenomegaly (characteristic)
- Severe haemorrhage:
- Due to Mast cells anticoagulant release (eg. heparin) & liver and splenic dysfunction
- Bone involvement:
- Osteoporosis
Diagnosis
Imaging
Abdominal ultrasound or computerized tomography (CT) scanning
- Hepatosplenomegaly and lymphadenopathy
Plain radiography and bone densitometry
- Assess bone involvement and the presence of osteoporosis
Investigations
Peripheral blood smear
Endoscopy and biopsy
- Suspected gut involvement
Managment
- Immunotherapy:
- Anti-IgE immunoglobulin
- Chemotherapy:
- Combination of: Cytosine arabinoside + idarubicin/daunomycin/mitoxantrone (as for acute myeloid leukaemia)
- Stem cell transplantation