Mast cell leukemia C94.3

Mastocytosis with systemic malignant mast cell proliferation and leaching of atypical mast cells into the peripheral blood

Especially patients with systemic mastocytosis without cutaneous skin involvement are at risk (approx. 30%).

Corresponding to mastocytosis.

>20% mast cells in the bone marrow aspirate, mast cells usually immature, often blastar. >10% mast cells in blood smear.

Both aggressive systemic mastocytosis (ASM) and mast cell leukemia require cytoreductive therapy because they are life-threatening.

Cytostatic drugs such as cyclophosphamide, chlorambucil and others can be tried. However, the chances of success are low.

Very serious, usually rapidly progressive course. Malignancy development is very rare in mastocytosis with skin involvement.

1. Arber DA et al (2016) The 2016 revision to the World Health Organization classification of myeloidneoplasms
   and acute leukemia. Blood 127:2391-405.
   
2. Torrey E et al (1990) Malignant mastocytosis with circulating mast cells. Am J Hematol 34: 283-286