A study led by Swedish researchers has demonstrated the potential of plasma protein biomarker profiling to discern systemic mastocytosis subtypes, as well as the cellular origin of the proteins. The study cohort included plasma samples from 16 patients with cutaneous mastocytosis (CM), 92 patients with systemic mastocytosis (indolent systemic mastocytosis (ISM), n=80; advanced systemic mastocytosis (AdvSM), n=12). A principal component analysis revealed a single cluster of patients with CM and ISM that was separated from patients with AdvSM. Moreover, up to 29 proteins were associated with distinct levels of severity in patients with differing subtypes of systemic mastocytosis. The researchers concluded that distinct plasma protein profiles potentially could be used to refine ISM and AdvSM diagnoses, provide further insights into disease mechanisms, and improve treatment.