The current recommendation (Wells et al. 2015, Haddad et al. 2018) is to consider treatment for tumours >1–2 cm in diameter growing >20% per year, or for symptomatic control: clearly depending on availability, one could use the selective RET-antagonists for germline or somatic RET-mutation-positive tumours and vandetaninib or cabozantinib when these are absent. Here, RET is linked to neoplasm.