Malignant Insulinoma: Diagnostic Difficulties and Treatment Strategies in a Case of Persistent Hypoglycemia

Hypoglycemia in non-diabetic individuals is a rare but critical condition that often signals an underlying pathology. Insulinoma, a rare neuroendocrine tumor of the pancreas, is a key differential diagnosis. As the most common functional pancreatic neuroendocrine tumors, insulinomas originate from pancreatic islet cells and are predominantly benign. However, malignant cases, although rare, represent a significant diagnostic challenge. Here, we report a 67-year-old female with recurrent hypoglycemic episodes presenting as diaphoresis and palpitations, alleviated by glucose intake. Initial tests revealed critically low blood sugar levels and elevated fasting insulin and C-peptide. Despite a normal abdominal CT, a PET-CT scan identified an exophytic pancreatic lesion with metastases to retroperitoneal lymph nodes, and malignancy was confirmed by histopathological examination. This case highlights the necessity of considering insulinoma in the differential diagnosis of unexplained hypoglycemia. Accurate and timely diagnosis, along with appropriate imaging and management, is crucial for effective treatment and improved patient outcomes.