Multicentric insulinoma associated with multiple endocrine neoplasia type 1: One case report

Pancreatic neuroendocrine tumors may be associated with multiple endocrine neoplasia type 1 (MEN1) in 15-25% of cases, and up to 10% develop insulinomas, which are the most frequent cause of persistent hyperinsulinemic hypoglycemia in adults. The objective is to show a clinical case that presents this association.

36-year-old patient with seizures associated with fasting hypoglycemia of 36 mg/dL. The patient presented high levels of insulin, peptide C, proinsulin, hypercalcemia, hypophosphatemia and parathyhroid hormone. Ultrasound sonography test showed hypoechoic lesion in the pancreatic tail of 2.3 cm. Tomography showed a 10 mm hypodense lesion at pancreatic head. Scintigram showed hypercaptating parathyroid tissue. Magnetic resonance did not show evidence of pituitary adenoma. We carried out a tumor enucleation of the pancreatic head and distal partial pancreatectomy with histopathological diagnosis of well-differentiated low-grade multifocal neuroendocrine tumor (five tumors); two tumors were immunoreactive to insulin. After surgery, glucose level was normalized (105 mg/dL). Patient underwent parathyroidectomy with a report of adenoma of the parathyroid gland.

The multicentricity of pancreatic neuroendocrine tumors related to parathyroid neoplasia suggests the diagnosis of MEN1. Genetic molecular studies should be performed to confirm this and provide the patient with a correct diagnosis, targeted treatment and adequate genetic counseling.