Systemic Mastocytosis with Associated Primary Myelofibrosis

Excerpt

Systemic mastocytosis (SM) is a chronic myeloproliferative neoplasm characterized by the infiltration of atypical mast cells (MC). The major SM diagnostic criterion is the multifocal clustering of mast cells in the bone marrow. Minor SM criteria include an abnormal MC morphology and expression of CD25/CD2, an activating mutation at codon 816 of KIT, and a persistent serum tryptase concentration of > 20 ng/mL. When the major and at least 1 minor criterion or 3 minor criteria are fulfilled, the SM diagnosis is established. The World Health Organization (WHO) classification has recently recognized a subgroup of SM with an associated hematological neoplasm (SM-AHN), which is characterized by the presence of a concurrent neoplasm [1]. We present the case of a 72-year old woman suffering from SM associated with myelofibrosis (MF) referred to our center due to mild anemia and leukocytosis (Hb, 10.2 g/dL, WBC, 11,900/mm³, PLT, 368,000/mm³). The patient complained of fatigue, pruritus and weight loss. Physical examination revealed splenomegaly; Jak2V617F mutation and c-kit D816V mutation were detected. Basal tryptase value was 80.4 ng/mL. …