GRPR and neoplasm: This can be assigned to a GPRR-specific process, given that during in vivo GRPR blockade at excess 40 nmol peptide dose uptake was banned in both pancreas (1.17 ± 0.11% ID/g; p < 0.001) and tumor (0.64 ± 0.10% ID/g; p < 0.001).