Unmasking an insulinoma: From biochemical to pathological diagnosis

An insulinoma is a rare pancreatic neuroendocrine tumour, which produces excess insulin resulting in symptomatic hypoglycemia. An 81-year-old woman, known for hypertension and osteopenia, was brought back to hospital after experiencing a recurrent episode of acute confusion and loss of consciousness; she had been seen 1 month earlier and diagnosed with a transient ischemic attack. While admitted to hospital, she had several witnessed episodes of altered mental status, during which time she was hypoglycemic. Critical blood samples were obtained that demonstrated a hyperinsulinemic hypoglycemia etiology. A CT scan of the abdomen and pelvis showed a hyper-enhancing lesion within the anterior pancreatic body, and a biopsy of the mass was consistent with a well-differentiated neuroendocrine tumor. The patient ultimately underwent partial pancreatectomy, and surgical pathology confirmed the diagnosis of an insulinoma. This case highlights the importance of strong clinical reasoning skills, coupled with biochemical and pathological findings, in the diagnosis and management of insulinoma.