SUN-309 Insulinoma Case Series: Experience of a Tertiary Care Center

Abstract

Background : Insulinoma is the most common functioning pancreatic neuroendocrine tumor. It’s an important endocrine etiology of obesity, which is characterized by a hyperinsulinemic hypoglycemia (HH). Case reports: Case 1: A 23 years old woman developed hypoglycemia symptoms and weight gain (13kg in 6 months). The prolonged fasting test (PFT) was performed: plasma glucose 29 mg/dL, C-peptide 2,6ng/mL (< 0,6 ng/mL), plasma insulin 29,9 μU/mL (< 3,0 μU/mL), showing a HH. Abdominal CT showed a 1.3 cm hypervascularity nodule, next to the distal portion of the pancreatic tail close to the vein and splenic artery. A successful partial pancreatectomy and splenectomy were performed and she remains asymptomatic. Case 2: A 41 years old man, with severe obesity Body Mass Index (BMI) 65 kg/m 2 and impaired fasting glucose presented HH (glucose 41 mg/dL, C-peptide 27,3 ng/mL, insulin 637 μU/mL) and weight gain. MRI showed a 3,0 cm hypervascularity nodule between the body and pancreas tail. Octreotide, diazoxide, dextrose continuous infusion pump and hydrochlorothiazide were prescribed to control hypoglycemia. Partial pancreatectomy and splenectomy were performed but in the postoperative period, patient developed renal failure, sepsis, acute respiratory distress syndrome and death. Case 3: A 21 years old woman with severe obesity (BMI 60 kg/m 2 ), after using intragastric balloon for 6 months, developed hypoglycemic symptoms, including seizures. The PFT showed plasma glucose 44 mg/dl, plasma insulin 47 μU/mL, C-peptide 3,2 ng/mL. MRI showed a 1.9 cm hypervascularity nodule in the cephalic portion of the pancreas, very close to cava vein. Diazoxide was prescribed with improvement of hypoglycemia. Due to the high surgical risk given the location of the tumor and obesity, an endoscopic ultrasound (EUS) guided ethanol ablation was performed. After the procedure, diazoxide was discontinued and two months later she had no hypoglycemia and is still loosing weight. Antiinsulin antibodies were negative and all biopsies confirmed insulinoma. Conclusion: Insulinomas can be a challenging diagnose and management. Once, most of the patients are overweight, the surgical treatment became a threat , therefore advanced techniques are an important advance for reducing mortality.