Abstract
Insulinomas are the most common cause of endogenous hyperinsulinemic hypoglycemia in non-diabetic adults. They are most often benign, small and difficult to localize with current imaging techniques. This is of high importance, as complete surgical resection is the only curative treatment. Anatomic imaging, (111)In-pentetreotide scan and (68)Gallium-DOTATATE positron emission tomography/computed tomography (PET/CT) were compared in a patient with insulinoma. (68)Gallium-DOTATATE PET/CT and selective arterial calcium stimulation localized the insulinoma. At surgery, a tumor in the anterior aspect of the pancreatic body was found which confirmed the preoperative localization, and a 2.1 cm tumor was enucleated, World Health Organization (WHO) grade I insulinoma. The patient remains euglycemic and free of symptoms at last follow up. In conclusion, (68)Gallium-DOTATATE PET/CT imaging may be a useful adjunct localizing study for insulinomas. It is a non-invasive preoperative localization study that could guide surgical exploration for successful therapy.