Keywords
Insulinoma
Neuroendocrine Tumors
Pancreatic Neoplasms Magnetic Resonance Imaging
Positron Emission Tomography Computed Tomography
Hyperinsulinism
Receptors
Somatostatin
Tomography
X-Ray Computed
Gallium
How to Cite
Abstract
Background: Pancreatic NeuroEndocrine Tumors are rare and heterogeneous neoplasm that can be classified into functional and non-functional, with differences in clinical presentation and prognosis. Insulinomas, the most frequent functional subtype, causes severe hypoglycemia due to uncontrolled insulin secretion. Its localization can be challenge, since conventional studies such as computed tomography (CT) and endoscopic ultrasound (EUS) can be inconclusive.
Purpose: To describe the stepwise strategy for localizing an insulinoma in a clinical case, with emphasis on the performance of Ga-68 PET/CT compared with other imaging modalities and its implications for management.
Case Presentation: 59-year-old woman with hypoglycemia due too endogenous hyperinsulinemia, in whom CT and EUS failed to detect the tumor. A PET/CT with gallium-68 identified a lesion in the pancreatic body, allowing a successful surgical resection and successful resolution and complete symptomatic resolution.
Discussion: Hypoglycemia in non-diabetic patients is characterized by symptoms consistent with low glucose levels that resolve upon normalization. When caused by endogenous hyperinsulinism, it is often due to insulinoma, the most common functioning pancreatic neuroendocrine tumor derived from beta cells. Diagnosis relies on Whipple’s triad, fasting tests, and measurement of insulin, C-peptide, and ketones. Tumor localization is essential for surgery and is supported by CT, MRI, and endoscopic ultrasound. Ga-68 PET/CT with somatostatin analogs provides high sensitivity, although indolent insulinomas may require GLP-1 receptor PET imaging. These techniques enable precise tumor detection and optimal surgical planning.
Conclusion: PET/CT has emerged as a fundamental tool for the localization of insulinomas when other methods fail, allowing a precise surgical approach and improving the management of these rare tumors.
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