Small nonfunctional pancreatic neuroendocrine neoplasms: Time for a step-up treatment approach?

Abstract

Surgery has been regarded as the only curative treatment for patients with small nonfunctional pancreatic neuroendocrine neoplasms (NF-PNENs) less than 2 cm. Due to the significant adverse event rates of surgery, the European Neuroendocrine Tumor Society issued guidelines favoring surveillance for those patients lacking criteria suggestive of an aggressive disease. Despite the above recommendations, a significant proportion of small NF-PNEN patients still undergo surgery. Recently, several studies have reported the safety and effectiveness of EUS-guided radiofrequency ablation (RFA) for the treatment of small NF-PNENs. The experience with EUS-RFA is, however, limited, but published results indicate a potential role as a minimally invasive alternative treatment for these patients, in particular in those in whom further progression is more probable, before they reach the absolute need for surgery. A step-up approach with EUS-RFA followed by surgery for the failure cases can become a valid option to be validated in clinical studies.

Keywords: EUS; Non-functional; Pancreatic neuroendocrine neoplasms; Radiofrequency ablation; Step-up treatment; Surgery.

Figure 1

Algorithm proposing a novel strategy including EUS-guided RFA for small incidental pancreatic nonfunctional neuroendocrine neoplasms. *Consider specific tumor site, patient’s age, and comorbidity; ^&A distance of the lesion less than 2 mm to the main pancreatic duct may represent a contraindication to EUS-RFA or require pancreatic duct stent placement; ^#Re-evaluation of tumor status should be performed every 6 months for the 1^st year, then annually if complete necrosis is obtained; ^$Repeat EUS-RFA can be considered. NF-PNENs: Nonfunctional pancreatic neuroendocrine neoplasms; CT: Computer tomography; MRI: Magnetic resonance imaging; EUS-FNB: EUS-guided fine-needle biopsy; RFA: Radiofrequency ablation; EUS-RFA: EUS-guided RFA