Insulinoma: Spectrum of Clinicopathological Features in a Tertiary Center

Abstract

Introduction:Insulinoma is the most common functional neuroendocrine tumor of the pancreas. There are different methods for the preoperative localization of insulinoma, such as Computed Tomography (CT) scan, Magnetic Resonance Imaging and Endoscopic Ultra Sonography (EUS). In this study, we report on the clinicopathological features of insulinoma in 43 patients.Methods:The hospital records of 43 patients with suspicion of insulinoma based on biochemical diagnostic criteria, referred to İmam Khomeini Complex Hospital, Tehran, Iran between 2006 and 2016, were reviewed retrospectively.Results:Of the 43 studied patients, 28 were female. The mean age of the patients was 45.4±13.3 years. The most frequent clinical presentation of insulinoma was neurogenic and neuroglycopenic symptoms (81.4%). Mean glucose, insulin, and C-peptide in patients with hypoglycemic crisis were 39.13±13.15 mg/dL, 32.15±32.53 μUI/mL, and 4.77±2.88 ng/mL, respectively. Mean tumor size was 2.13±1.22 cm. The most common site of insulinoma was the tail of the pancreas. Surgery was the treatment of choice and performed in 31 patients. Of 21 tumors studied microscopically, 7 were invasive.Conclusion:In non-diabetic patients with manifestations of hypoglycemia, a diagnosis of insulinoma should be considered. During the past decade, the diagnostic delay for insulinoma has been reduced in our country by improving imaging technologies. EUS and CT scan are the best modalities for localization and size measurement of insulinoma. Tumor size has decreased compared with previous decades, probably due to a reduced delay in diagnosis.

Keywords

• insulinoma
• hypoglycemia
• neoplasm
• pancreas