KIT and neoplasm: 4 and 11, whereas the primary lesions showed wild-type KIT. It is interesting to note that patient No. 4 showed not only a KITV560G mutation in CTC, but also a BRAFV600E mutation in the primary tumour, as well as in another CTC (Figure 2B); this is unusual because mutations in BRAF and KIT are thought to be mutually exclusive (Curtin et al, 2006; Carvajal et al, 2011).