In our study, the correlation between histological PSMA expression and the uptake in PSMA PET was dependent on the size of the analysed tumour volumes and areas: Spearman’s coefficients of H-Score to SUVmean and SUVmax were clearly, in part significantly, higher for the tumour volumes with an in-vivo volume over 1 ml and the tumour areas with a histological area over 400 μm2. Here, FOLH1 is linked to neoplasm.