Radiofrequency ablation of solitary pancreatic insulinoma in a patient with episodes of severe hypoglycemia

For the 60-year period from 1927 through 1986, we assessed the incidence, recurrence, and long-term survival among all Mayo Clinic patients with histologically confirmed functioning insulinoma. With use of the complete medical record system at Mayo and the comprehensive epidemiologic data base of residents of Olmsted County, Minnesota, we found 224 patients in whom an initial pancreatic exploration at Mayo had confirmed the presence of insulinoma. The median age (and range) of these patients at surgical diagnosis was 47 (8 to 82) years, and 59% were female patients. During the study period, eight cases of insulinoma occurred among residents of Olmsted County; their age and gender distributions were similar to those of the total cohort. The incidence of insulinoma among residents of Olmsted County increased during the study period to a stable level during the last 2 decades of 4 cases per 1 million person-years. For the total cohort, 7.6% had multiple endocrine neoplasia type I (MEN I), and 5.8% had malignant insulinoma. The risk of recurrence was greater among patients with MEN I (21% at 10 and 20 years) than in those without MEN I (5% at 10 years and 7% at 20 years). Although survival of the total cohort was not significantly impaired, it was significantly worse than expected for patients with malignant insulinoma (29% versus 88% expected at 10 years postoperatively). We conclude that insulinoma is less rare than previously suspected. After successful surgical removal, the long-term risk of recurrent insulinoma is relatively high in patients with MEN I; for patients with benign disease, the long-term survival is normal.

The reported experience with laparoscopic pancreatic resections (LPR) remains limited to case reports or small series of patients. A retrospective multicenter study was conducted in 25 European surgical centers concerning their experience with LPR. Detailed questionnaires were used, focusing on patients, tumors, operative data, and late outcome. During the study period, 127 patients with presumed pancreatic neoplasms were enrolled in this series. Final diagnoses included benign pancreatic diseases in 111 patients (87%; insulinoma: 22, neuroendocrine neoplasm: 20, mucinous cystadenoma: 26, serous cystadenoma: 21, chronic pancreatitis: 11, others: 11), and 16 patients (13%) had malignant pancreatic diseases (insulinoma: 3, neuroendocrine neoplasm: 5, ductal adenocarcinoma: 4, cystadenocarcinoma: 2, renal metastases: 2). Five patients with presumed benign pancreatic disease had malignancy at final pathology. The median tumor size was 30 mm (range, 5-120 mm); 89% of tumors were located in the left pancreas. Laparoscopically successful procedures included 21 enucleations, 24 distal splenopancreatectomies, 58 distal pancreatectomies with splenic preservation, and 3 pancreatoduodenal resections. The overall conversion rate was 14%. There were no postoperative deaths. The rate of overall postoperative pancreatic-related complications was 31%, including a 17% rate of clinical pancreatic fistula. The surgical reoperation rate was 6.3%. In laparoscopically successful operations, the median postoperative hospital stay was 7 days (range, 3-67 days), decreased compared with patients requiring conversion to open pancreatectomy. During a median follow-up of 15 months (range, 3-47 months), 23% of the patients with pancreatic malignancies had tumor recurrence. Late outcome was satisfactory in all patients with benign diseases. LPR is feasible and safe in selected patients with presumed benign and distal pancreatic tumors. The management of the pancreatic stump remains a challenge. The role of LPR for pancreatic malignancies remains controversial.

Surgical resection is currently considered to be the criterion standard for treatment of insulinomas. Alternative treatments, despite medication with diazoxide, are lacking. EUS-guided ethanol ablation of endocrine tumors has not been reported before. A 78-year-old woman was referred with typical symptoms of an insulinoma. Diagnosis was confirmed by laboratory findings, EUS, and EUS-guided FNA. Because of severe complications during several hypoglycemic episodes, a poor general condition, and strict refusal of surgical resection, the decision was made to ablate the insulinoma by EUS-guided alcohol injection. A total of 8 mL 95% ethanol was injected into the tumor. The patient was discharged and exhibited no further hypoglycemic episodes, and her general condition improved rapidly. Based on clinical, morphologic, and biochemical criteria, we achieved a durable complete remission of the tumor. EUS-guided ablation may become a minimally invasive alternative for patients with insulinomas in whom surgery is not feasible.