Supplementary Material for: Evaluation of the Site and Frequency of Lymph Node Metastasis with Non-Functioning Pancreatic Neuroendocrine Tumor

Backgrounds: The optimal lymph node dissection range in patients with non-functioning pancreatic neuroendocrine tumors is not yet clear. In this study, we investigated the site and frequency of lymph node metastasis and the significance of lymph node dissection in patients with non-functioning pancreatic neuroendocrine tumors. Methods: This retrospective study analyzed 74 patients who underwent a curative pancreatectomy for non-functioning pancreatic neuroendocrine tumors between 2000 and 2016. The site and frequency of lymph node metastasis and clinicopathological factors were evaluated. Results: The rate of synchronous lymph node metastasis was 17.6%, with 11.1 and 29.4% for tumors with diameters of 10–19 mm and ≥20 mm, respectively. Lymph node metastasis was not observed for tumors with a diameter Conclusions: This study clarified the site and frequency of lymph node metastasis and the optimal range of lymph node dissection in patients with non-functioning pancreatic neuroendocrine tumors.