ENTPD1 and mucoepidermoid carcinoma: Apart from a single study that investigated CD73 expression levels in acinic cell carcinomas (ACC) and mucoepidermoid carcinoma (MEC), the present study is the first to comprehensively analyze CD39 and CD73 expression levels across a large spectrum of SGCs to identify promising subtypes for adenosine pathway inhibition, especially for those entities in which the blockade of PD-1/PD-L1 was shown to be ineffective (Cohen et al. 2018; Ranjbar et al. 2019).