Long-term outcome after EUS-guided radiofrequency ablation: Prospective results in pancreatic neuroendocrine tumors and pancreatic cystic neoplasms

Background and study aims Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) for pancreatic neuroendocrine tumors (NETs) and intraductal pancreatic mutinous neoplasia (IPMN) with worrisome features or high-risk stigmata (WF/HRS) has been evaluated in few series with short-term outcomes. This study's primary end-point was to assess the long-term efficacy of EUS-RFA in patients with NETs or pancreatic cystic neoplasms (PCNs) over at least 3 years. Patients and methods Twelve patients had 14 NETs with a mean 13.4-mm size (10-20) and 17 patients had a cystic tumor (16 IPMN, 1 MCA) with a 29.1-mm mean size (9-60 were included. They were treated with EUS-guided RFA, evaluated prospectively at 1 year, and followed annually for at least 3 years. Results The mean duration of follow-up was 42.9 months (36-53). Four patients died during follow-up (17-42 months) from unrelated diseases. At 1-year follow-up, and 85.7% complete disappearance was seen in 12 patients with 14 NETs. At the end of follow-up (45.6 months), complete disappearance of tumors was seen in 85.7% of cases. One case of late liver metastasis occurred in a patient with initial failure of EUS-RFA. At 1-year follow-up, a significant response was seen in 70.5% of 15 patients with PCNs. At the end of the follow-up, there was a significant response in 66.6% with no mural nodules. Two cases of distant pancreatic adenocarcinoma unrelated to IPMN occurred. Conclusions EUS-RFA results for pancreatic NETs or PCNs appear to be stable during 42 months of follow-up.