Detection of insulinoma using ⁶⁸Gallium-DOTATATE PET/CT: a case report

Insulinomas are the most common cause of endogenous hyperinsulinemic hypoglycemia in nondiabetic 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, ¹¹¹In-pentetreotide scan and ⁶⁸Gallium-DOTATATE positron emission tomography/computed tomography (PET/CT) were compared in a patient with insulinoma. ⁶⁸Gallium-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, ⁶⁸Gallium-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.