PECAM1 and neoplasm: Interestingly, while epithelial cell density, CD31-derived MVD, and epithelial MCT1 expression were similar between the two tumour types (Fig. 5d, e), ICC lesions with no discernible [1-13C]lactate labelling or measurable kPL showed almost negligible epithelial LDH density together with a marked increase in epithelial MPC2, FASN, and AR expression (Fig. 5d, e).