Malignant conversion and peritoneal dissemination after endoscopic ultrasound-guided ethanol ablation in intraductal papillary mucinous neoplasm of the pancreas

Background: With the increasing detection of pancreatic cysts, many centers have applied endoscopic ultrasound-guided pancreatic cyst ablation (EUS-PCA), even in intraductal papillary mucinous neoplasms (IPMNs) of the pancreas based on early promising outcomes. However, long-term effects of ethanol ablation have been rarely reported, especially regarding oncologic outcomes. Methods and Results: We report eight cases of malignancy conversion after EUS-PCA in patients with IPMNs who had worrisome features. Moreover, two patients showed tumor spillage or peritoneal seeding (carcinomatosis) after EUS-PCA. Conclusions: Endoscopic ultrasound-guided pancreatic cyst ablation must not be performed as a treatment for IPMNs, considering adverse results such as tumor spillage and the lack of oncological therapeutic effect.