Radio-frequency ablation for symptom control in a patient with metastatic pancreatic insulinoma

Malignant insulinomas are very rare endocrine tumours with a variable clinical course. We describe a 51-year-old man who had two large insulinomas resected from the body of the pancreas and 19 years later, having again become symptomatic, was found to have hepatic metastases. Medical treatment with diazoxide and octreotide failed to control his symptoms, but repeated hepatic embolization effected both symptomatic and biochemical improvements for a further 5 years. When symptoms recurred but further embolization failed to control his symptoms the hepatic metastases were treated by outpatient percutaneous radio-frequency ablation. He remains symptom-free 18 months later and levels of insulin and pro-insulin have nearly normalized. The survival, with liver metastases, for 27 years in a man with a malignant insulinoma has not been described previously. Malignant insulinoma may follow a rather indolent course and symptoms respond well to locally destructive therapies. Hepatic embolization is less traumatic than hepatic lobe resection and radio-frequency ablation offers an alternative if vascular access to the tumour is no longer possible.