label: Aggressive Systemic Mastocytosis
label_lc: aggressive systemic mastocytosis
description: "An aggressive and progressive mast cell neoplasm characterized by systemic infiltration of internal organs by aggregates of neoplastic mast cells. There is no evidence of mast cell leukemia or clonal hematologic malignancy. Clinical symptoms include hepatomegaly, splenomegaly, portal hypertension, malabsorption syndrome, and pathologic fractures."