Analysis of 6,747 Pancreatic Neuroendocrine Tumors for a Proposed Staging System

Currently, no reasonable staging system exists for pancreatic neuroendocrine tumors (PNET) to guide treating physicians. The aim of this study was to devise a staging system of relevant prognostic factors to better predict overall survival in PNET. A prospective 300 patient cohort and a review of the Surveillance Epidemiology and End Results database identified 6,447 patients with PNET from 1973 to 2008. Significant prognostic factors were created for an initial. Tumor: T (T1: a parts per thousand currency sign3 cm and localized to pancreas, T2: > 3 cm and localized to the pancreas; T3: extension to adjacent organs and vessels), grade: G (G1: well/moderate and G2: poor/undifferentiated), and metastasis: M (M0: no distant mets, M1: distant mets) staging system. Significant predictors of survival on multivariate analysis included age, size, grade, and metastasis. Based on the TGM staging system: stage 1 (T1-2, G1, M0), stage 2 (T1-2, G2, M0), stage 3 (T3G2M0, Tany, G1, M1), stage 4: (Tany, G2, M1) was created with survival being statistically different between stages (p < 0.0001). Median survival rates were stage 1, 55 months; stage 2, 50 months; stage 3, 46 months; and stage 4, 25 months. Incorporation of this newly developed staging system into clinical practice will improve the ability to predict prognosis and aid in stratification of patients for clinical trials.