FOLH1 and prostate cancer: Functional imaging of cells expressing PSMA using radiolabelled ligands, e.g. 68Gallium-PSMA-HBED-CC (also called 68Gallium-PSMA-11) and positron emission tomography combined with computed tomography (commonly referred to as PSMA PET/CT), is primarily used for the detection and (re)staging of prostate cancer [14].