Recurrence of malignant insulinoma in the context of multiple endocrine neoplasia type 1: a case report.

Insulinomas are rare pancreatic neuroendocrine tumors, typically benign, but in the context of multiple endocrine neoplasia type 1 (MEN1), they can be malignant and recurrent. This case report presents a 58-year-old man with MEN1 who initially underwent partial pancreatectomy for a malignant insulinoma in the pancreatic tail in 2019. Despite recurrence in 2021, the patient declined surgery; however, in 2025, he presented with hypoglycemia and imaging revealed a 3-cm mass in the pancreatic head. He underwent a Whipple procedure, with histopathological analysis confirming the recurrent insulinoma. This case highlights the clinical challenge of managing malignant insulinomas in MEN1, emphasizing the importance of long-term follow-up and staged surgical interventions due to the high risk of recurrence.