A case of ‘smouldering’ mastocytosis with high mast cell burden, monoclonal myeloid cells, and C-KIT mutation Asp-816-Val

• Published in: Leukemia research 2001-07, Vol.25 (7), p.627-634
• Main Authors: Jordan, John-Hendrik, Fritsche-Polanz, Robert, Sperr, Wolfgang R., Mitterbauer, Gerlinde, Födinger, Manuela, Schernthaner, Gerit-Holger, Christian Bankl, Hans, Gebhart, Walter, Chott, Andreas, Lechner, Klaus, Valent, Peter
• Format: Article
• Language: English
• Subjects: Adult; Amino Acid Substitution; Anemia - etiology; Biological and medical sciences; Bone Marrow - pathology; Cell Count; Classification; Clone Cells - chemistry; Clone Cells - pathology; Codon - genetics; Disease criteria; Disease Progression; DNA Mutational Analysis; Dosage Compensation, Genetic; Female; Hematologic and hematopoietic diseases; Humans; Hypotension - etiology; Mast Cells - pathology; Mastocytosis; Mastocytosis - complications; Mastocytosis - drug therapy; Mastocytosis - genetics; Mastocytosis - pathology; Medical sciences; Mutation, Missense; Myeloid Cells - chemistry; Myeloid Cells - pathology; Other diseases. Hematologic involvement in other diseases; Prognosis; Proto-Oncogene Proteins c-kit - genetics; Receptors, Androgen - analysis; Serine Endopeptidases - blood; Shock - etiology; Syncope - etiology; Tryptases; Urticaria Pigmentosa - complications; Urticaria Pigmentosa - drug therapy; Urticaria Pigmentosa - genetics; Urticaria Pigmentosa - pathology
• ISSN: 0145-2126; 1873-5835
• DOI: 10.1016/S0145-2126(01)00019-4

Mastocytosis is a term used for a group of disorders characterized by abnormal growth and accumulation of tissue mast cells (MC) in one or more organ systems. In patients with systemic mastocytosis (SM) the clinical course may be indolent or aggressive or even complicated by leukemic progression or an associated clonal hematologic non mast cell lineage disease (AHNMD). However, at first presentation (diagnosis) it may be difficult to define the category of disease and the prognosis. We report on a 48-year-old female patient with SM with urticaria pigmentosa-like skin lesions and mediator-related symptoms. She was found to have splenomegaly, a high infiltration grade (MC) in bone marrow biopsies (>30%), mild anemia, and a high serum tryptase level (>500 ng/ml). In addition, she exhibited discrete histologic signs of myeloproliferation in the ‘non-affected’ marrow and monoclonal blood cells established by C-KIT 2468A → T mutation (Asp-816-Val) -analysis and HUMARA assay. Despite these findings, however, the clinical course was stable over years and no AHNMD or organ impairment developed. Because of the ‘intermediate’ clinical signs and absence of progression to aggressive disease, we proposed the term ‘smouldering mastocytosis’.