Objective To explore the prognostic importance and preoperative predictors of lymph node metastasis in an effort to guide surgical decision making in patients with pancreatic neuroendocrine tumors (PNETs). Logistic regression was Poliumoside used to identify predictors of nodal metastasis. Overall survival (OS) and disease-free survival (DFS) were calculated using Kaplan Meier method. Results were expressed as value <0.05). Median DFS was lower for patients with nodal metastases (4.5 v 14.6 years < 0.0001). Conclusions Lymph node metastasis is usually predictive of poor outcomes in patients with PNETs. Preoperative variables are not able to reliably predict patients where the probability of lymph node involvement was less than 12%. These data support inclusion of regional lymphadenectmy in patients undergoing pancreatic resections for PNET. Introduction Pancreatic neuroendocrine tumors (PNET) are uncommon accounting for only 1-2% of all pancreatic malignancies . The incidence in the United States was 5.25 per 100 0 in 2004 compared to 1.09 in 1973 . The rise in incidence is likely in part due to improvement of imaging techniques . The biologic behavior and clinical outcomes of PNETs varies greatly and while the majority are relatively benign slow growing and non-infiltrative a subset is usually aggressive rapidly metastasizing and locally invasive. PNETs can also be divided into functional and nonfunctional based on hypersecretion of biologically active hormones resulting in clinical syndromes . The natural history of PNETs is usually consequently highly variable with the majority having a more favorable outcome and longer OS after surgical resection compared to pancreatic adenocarcinoma . Bilimoria K.Y. et al reported 5 and 10 years OS after surgical resection of PNET as 59.3% and 37.7% respectively . The mainstay of treatment for non-metastatic PNETs is usually medical procedures [7 8 The often indolent disease course and uncommon incidence of PNETs presents a considerable challenge to prospective study. Retrospective reviews with highly variable long term follow up have contributed to variable practice patterns. In addition many studies have inadequate or inconsistent lymph node sampling while others lack consistent pathological evaluation . As a Poliumoside result the importance of lymph node metastasis on survival and recurrence remain uncertain. Some studies exhibited the prognostic importance of nodal metastasis as a prognostic factor for PNET [10 11 while others failed to find any such association [6 12 Pancreatic resections are associated with significant morbidity  and there is interest in minimizing the impact of surgery. Enucleation and central pancreatectomy in selected patients utilizing in the beginning open and more recently with minimally invasive techniques has been reported [14-16]. These procedures have low morbidity and shorter hospital stay compared to standard pancreatectomy [14-16]. However it remains Poliumoside difficult to predict which tumors are appropriate for enucleation because we don’t have a validated way to determine which tumors are unlikely to have metastasized. Prior studies reported controversial results regarding the predictors of nodal metastasis [17 18 As a result the surgical approach and indications for lymph nodes dissection in PNET remain unclear. In this retrospective review of a prospectively managed institutional database we decided which pre-operative factors were associated with lymph nodes metastasis. Rabbit Polyclonal to MAP3K6. We further decided associations between lymph node metastases and survival (DFS and OS). Our goal was to attempt to identify a low risk group where regional lymphadenectomy could be eliminated and limited resection (enucleation central pancreatectomy etc.) would be appropriate. Ninety-eight percent of the patients included in this study underwent regional lymph nodes sampling placing us in a unique position to look at this question. Patients and methods Patients who underwent surgery for main PNETs between 1994 and 2012 were recognized from a retrospective review of a prospectively managed database at Barnes-Jewish Hospital Washington University School of Medicine. Patients who were lost to follow up or experienced distant metastasis (M1 status) were excluded. Demographic and clinical data were collected including age gender race presence of multiple endocrine neoplasm and functional status. Tumor characteristics including tumor size location grade Poliumoside Ki-67% perineural lymphovascular invasion surgical margin and lymph node status were reviewed. In cases where Ki-67 % was not reported slides were cut stained and.