Prognostic Value of the Regional Lymph Node Station in Pancreatic Neuroendocrine Tumor

Background/Aim: Little is known regarding the impact of lymph node dissection on survival benefit after curative resection for pancreatic neuroendocrine tumor (PNET). This study aimed to evaluate the efficacy of lymph node dissection based on tumor location of PNET. Patients and Methods: A retrospective study, including 50 patients with surgical resection for PNET between 2004 and 2020, was performed. The efficacy index (EI) was calculated by multiplication of the incidence of lymph node metastasis (LNM) at the station and the 5-year survival rate of patients with LNM at the station. Results: In the pancreatic head tumors, the peri-pancreatic head and superior mesenteric artery lymph node stations had high EI of 13.3 and 25, respectively. In contrast, other stations, including stations 8 and 12, had zero EI. In the pancreatic body and tail tumors, only the splenic artery lymph node station had a survival benefit from lymph node dissection with an EI of 6.7. Conclusion: The extent of lymph node dissection for PNET should be decided based on the efficacy of lymph node dissection in accordance with tumor location. Our findings may be helpful in determining the extent of lymph node dissection required.