CD274 and neoplasm: Since our previous study, several groups have confirmed higher and more diffuse tumour and immune cell PD-L1 staining in a subset of patients with ATC.14,37 These data are particularly relevant since high PD-1 and PD-L1 expression may correlate with poorer outcomes in ATC, and PD-L1 upregulation has also been shown to be a mechanism of resistance to BRAF inhibition.22,38