[CT segítségével/Localization of a small insulinoma with the aid of 68Ga-exendin PET/CT]

The hyperinsulinemic hypoglycemic syndrome is typically caused by insulinoma, a neuroendocrine tumor of the pancreas. Beyond the diagnosis, the most difficult part is the accurate localization of the tumor, which is essential to the curative surgical therapy. A 36-year-old woman with several episodes of loss of consciousness was diagnosed with endogenous hyperinsulinemia causing hypoglycemia. The MRI raised the possibility of a 5-mm lesion in the tail of the pancreas, however, neither the CT, nor the endoscopic ultrasound was able to confirm it. The somatostatin-receptor scintigraphy was also negative. The 68Ga-exendin PET/CT showed tracer enhancement in the tail of the pancreas in the same region as in the MRI. Based on these results, a distal pancreas resection was made. After the surgery, the hypoglycemic episodes of the patient disappeared and histology confirmed the diagnosis. Conventional imaging techniques are often not sensitive enough for the localization of insulinoma, mostly in cases of small, hypovascularized tumors. Somatostatine-receptor targeted modalities which are widely used in the imaging of neuroendocrine tumors could be negative because of the lower expression of somatostatine receptors. In our case, the novel, functional imaging 68Ga-exendin PET/CT was efficiently used, which can localize insulinomas with high sensitivity. Orv Hetil. 2025; 166(6): 228–233.