Clinical Value of 18F-FDOPA PET/CT With Contrast Enhancement and Without Carbidopa Premedication in Patients with Insulinoma

Abstract

Aim: We evaluated the clinical usefulness of 6-[¹⁸F]fluoro-3,4-dihydroxy-L-phenylalanine(¹⁸F-FDOPA)-positron-emission tomography (PET)/computed tomography (CT) in insulinoma detection with contrast enhancement, early acquisition time, and no carbidopa premedication.

Patients and methods: Twenty-six patients diagnosed with hyperinsulinemic hypoglycemia underwent an ¹⁸F-FDOPA PET/CT examination. Patients without carbidopa premedication and contrast-enhanced CT were included. Imaging findings were compared to the overall final diagnosis (histological findings).

Results: In 10 of 26 patients (eight women, two men; mean age=53 years; age range=30-94 years), a detected lesion was confirmed histologically as an insulinoma. ¹⁸F-FDOPA PET detected the tumor in five out of ten patients. Contrast-enhanced CT also detected the tumor in five out of ten. Overall, ¹⁸F-FDOPA PET/CT, with contrast enhancement and without carbidopa premedication, was able to detect the insulinoma in seven out of ten patients (70%).

Conclusion: Based on our data, ¹⁸F-DOPA PET/CT, with contrast enhancement and without carbidopa premedication, as a 'one-stop' diagnostic modality is a viable option for insulinoma detection.

Keywords: 18F-FDOPA; 18F-fluorodihydroxyphenylalanine; CT; Insulinoma; PET; carbidopa; computed tomography; positron emission tomography.