The receptor tyrosine kinase KIT, a mast cell signature protein, has been associated with circulating EVs from patients with systemic mastocytosis (Kim et al., 2021, 2018), acute myeloid lymphoma (Boyiadzis & Whiteside, 2017; Hong et al., 2014; Szczepanski et al., 2011), EVs released by neoplastic mast cells (Kim et al., 2018; Kim et al., 2021; Xiao et al., 2014), activated mast cells (Groot Kormelink et al., 2016; Liang et al., 2020), and GIST cells (Atay et al., 2014, 2018). The gene discussed is NTRK1; the disease is systemic mastocytosis.