Mast cell leukemia

The most severe subtype of SM, caused by the rapid buildup of immature mast cells in the bone marrow and blood. Mast cell leukemiaMast cell leukemia The most severe subtype of SM, caused by the rapid buildup of immature mast cells in the bone marrow and blood. Mast cell leukemia accounts for less than 5% of SM cases and has a poor prognosis. accounts for less than 5% of SM cases and has a poor prognosis.