Mast cell disease associated with acute myeloid leukemia: detection of a new c-kit mutation Asp816His.

Mast cell disease (MCD), a proliferation of mast cells (MC), is occasionally associated with hematologic malignancies. Neoplastic MC have activating c-kit mutations. c-kit is a receptor tyrosine kinase required for the development, proliferation, and survival of MC. Interaction of c-kit with its ligand stem cell factor induces dimerization, receptor phosphorylation, and signal transduction. The most common c-kit mutation detected in neoplastic MCD is Asp816Val, which results in ligand-independent autophosphorylation of the receptor leading to MC proliferation. We describe the rare occurrence of MCD associated with acute myeloid leukemia, report a novel c-kit mutation Asp816 His, and discuss the pathogenesis of MCD associated with hematologic malignancies.