For imaging of insulinoma lesions, a variety of exendin-4-based ligands have been or are currently investigated in clinical trials for targeting the glucagon-like peptide 1 receptor (GLP-1R) (Jansen et al., 2019; https://clinicaltrials.gov/ct2/results?cond=Insulinoma&term=glp-1R&cntry=&state=&city=&dist=&Search=Search, 2020). This evidence concerns the gene GLP1R and pancreatic insulinoma.