EUS-guided radiofrequency ablation for management of pancreatic insulinoma by using a novel needle electrode (with videos)

Background and Aims: Insulinomas are one of the most common functional pancreatic neuroendocrine tumors. Surgical removal is the standard of care. Patients unfit for or refusing surgery need an alternative nonsurgical method to alleviate symptoms. EUS has been used to localize, aspirate, and tattoo insulinomas and to inject alcohol for local ablation. This study is aimed at assessing the feasibility of EUS-guided radiofrequency ablation (EUS-RFA) for managing patients with a symptomatic insulinoma by using a novel EUS-RFA needle electrode. Methods: The EUS-RFA system used consists of a prototype 19-gauge needle electrode, generator, and internal cooling system. EUS-guided RFA is performed under real-time visualization at 50 W to ablate pancreatic insulinomas. Results: In this observational human case series from a tertiary care center, 3 patients with a symptomatic pancreatic insulinoma, not eligible for surgery, underwent EUS-RFA by using an internally cooled prototype needle electrode. All had rapid symptom relief with biochemical improvement and remained symptom free at 11 to 12 months of follow-up. There were no procedure-related adverse events. Conclusions: EUS-RFA with the novel device can be considered in select patients with a symptomatic pancreatic insulinoma based on preliminary findings of a beneficial effect without adverse events. Assessment of the safety profile requires larger prospective trials. An insulinoma is the most common functional pancreatic neuroendocrine tumor (PNET), with the majority (90%) being small (<2 cm) and benign. The associated debilitation is related to hypoglycemia secondary to excessive uncontrolled insulin production. Whipple’s triad helps to identify insulinomas. Increased fasting serum insulin and C-peptide assist in the diagnosis. Surgery is the standard of care for PNETs, with occasional adverse events including pancreatic fistulae and deep vein thrombosis leading to a pulmonary embolism. Patients unfit for or refusing surgery require alternative treatment. 1 Medical therapy is costly and may have significant adverse effects. Embolization and ablation are options. 2-25