An insulinoma is the most common functional pancreatic neuroendocrine tumor (pNET). Increased fasting serum insulin and C-peptide assist in the diagnosis. Surgery is the standard of care for pNET. However, it can lead to complications such as diabetes mellitus. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is a promising therapy for treatment of pancreatic neoplasms.
The purpose of this study is to assess the safety and clinical effectiveness of EUS-RFA in pancreatic tumors.
Systematic review based on searching eight national databases including KoreaMed and three international databases including Ovid-MEDLINE, Ovid-EMBASE, and Cochrane Library. After having excluded 1,583 articles (including 386 duplicated articles), 11 articles (7 case series and 4 case reports) were reviewed in the final assessment. The article quality was evaluated using Scottish Intercollegiate Guidelines Network (SIGN), and the level of evidence and grade of recommendation were carefully determined and documented based on the quality.
In the safety, there was no procedure related death. One of the studies reported severe complications(10%, acute pancreatitis with fever, perforation, a stenosis of the main pancreatic duct), but those that were appropriately treated and the tumors had completely disappeared at follow-up. After the therapy, clinical response with normalization of glucose levels was observed in all insulinoma cases. Also, radiological complete response was reported in most of patients and some cases remained symptom free at 10 to 12 month of follow-up. As a result, EUS-RFA has an effectiveness to improve symptom through ablating the tumors. We suggest that EUS-RFA can be used before the surgery. On the other hand, there was lack of evidence to assess clinical effectiveness in pancreatic cancer and the studies reported a low complete response rate(25~64.7%) in non-functional pNET and cystic tumors. Therefore, in pancreatic adenocarcinoma, non-functional pNET and cystic neoplasms, further research is required in the form of long-term follow up(more than 5 years) study design(Level of Evidence D).
Finally, EUS-RFA of insulinoma with symptom(≤2cm) is a minimally invasive, safe and clinical effectiveness. We concluded that more data about clinical effectiveness, long-term results were needed in the other indications.