Cytogenetic abnormalities in systemic mastocytosis: WHO subcategory-specific incidence and prognostic impact among 348 informative cases

Abstract

The World Health Organization (WHO) system lists five morphological categories of systemic mastocytosis (SM): indolent (ISM), smoldering, SM with an associated hematological neoplasm (SM-AHN), aggressive (ASM) and mast cell leukemia (MCL). Recent studies have highlighted the prognostic importance of mutations in SM, including ASXL1, RUNX1, and SRSF2. In contrast, information on incidence of cytogenetic abnormalities in SM and their prognostic relevance, especially in the context of mutations, is limited. In the current study, we retrospectively reviewed the cytogenetic findings in 348 consecutive cases of SM (median age 59 years; 53% males); 41% constituted ISM, 45% SM-AHN, 14% ASM and two cases of MCL. Karyotype was abnormal in 53 (15%) cases with incidences of 6% for ISM, 26% for SM-AHN and 8% for ASM (P 60 years (P =.04), thrombocytopenia (P