Poor Applicability of Currently Available Prognostic Scoring Systems for Prediction of Outcome in <em>KIT</em> D816V-Negative Advanced Systemic Mastocytosis

Within our nationwide registry, we identified a KIT D816V mutation (KIT D816V^(pos.)) in 280/299 (94%) patients with advanced systemic mastocytosis (AdvSM). Age, cytopenias and the presence of additional somatic mutations confer inferior overall survival (OS). However, little is known about the characteristics of KIT D816V-negative (D816V^(neg.)) AdvSM. In 19 D816V^(neg.) patients, a combination of clinical, morphological and genetic features revealed three subgroups: (a) KIT D816H- …