Insulinoma: um diagnóstico que deve ser sempre lembrado frente a sintomas de hipoglicemia. Relato de dois casos

Abstract

Insulinomas are rare tumors originated from the beta cells of the pancreas islets. They are generally benign, small, unique and equally distributed throughout the pancreas, with higher incidence on individuals aging between 40 and 60 years old. Its clinical aspects are characterized by episodes of symptomatic hypoglycemia that occur as a consequence of high amounts of insulin secreted by the tumor. The diagnosis of insulinoma is given combining data from anamnesis and physical exams along with laboratory tests and, due to its rareness, the hypersecretion of insulin is hardly ever settled as the cause of hypoglicemia on the first evaluation of the patient. The purpose of reporting these two cases is to call physicians’ attention to a possible diagnosis of insulinoma when the patient shows inespecific symptoms like dizziness, syncope and sweat. The patients in the report were only diagnosed with insulinoma after going through several medical services, for at least 7 years, due to these symptoms. Diagnoses were confirmed by a 72-hour-fast test, which showed low serum levels of glucose and high insulin and C-peptide levels, suggestive of the syndrome. The localization of the tumors was achieved by magnetic resonance imaging and computerized tomography of abdomen, with dimensions measuring approximately 2 cm in both cases. After surgical resection, the patients had the histological diagnosis confirmed of insulinoma, with tumor free margins, and maintained favorable clinical and laboratorial evolution.