This study investigated the utility of a novel PEGylated exendin-4-based probe for PET imaging, [18F]FB(ePEG12)12-exendin-4, for insulinoma detection using Pdx1-Cre;Trp53R172H;Rbf/f mice and conventional model mice bearing insulinoma xenografts. This evidence concerns the gene PDX1 and pancreatic insulinoma.