Perspectives International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) & European Competence Network on

Systemic mastocytosis (SM) is charac-terized by accumulation of neoplastic mast cells and is classified into indo-lent and aggressive forms. The latter include aggressive SM (ASM), mast cell leukemia (MCL), and SM associated with a myeloid neoplasm wherein 1 or both disease compartments exhibit advanced features. These variants, henceforth col-lectively referred to as advanced SM for the purposes of this report, are typi-cally characterized by organ damage and shortened survival duration. In contrast to indolent SM, in which symp-toms are usually managed by noncyto