Nomogram predicting the risk of recurrence after curative‐intent resection of primary non‐metastatic gastrointestinal neuroendocrine tumors: An analysis of the U.S. Neuroendocrine Tumor Study Group

Background The risk of recurrence after resection of non‐metastatic gastro‐entero‐pancreatic neuroendocrine tumors (GEP‐NET) is poorly defined. We developed/validated a nomogram to predict risk of recurrence after curative‐intent resection. Methods A training set to develop the nomogram and test set for validation were identified. The predictive ability of the nomogram was assessed using c‐indices. Results Among 1477 patients, 673 (46%) were included in the training set and 804 (54%) in y the test set. On multivariable analysis, Ki‐67, tumor size, nodal status, and invasion of adjacent organs were independent predictors of DFS. The risk of death increased by 8% for each percentage increase in the Ki‐67 index (HR 1.08, 95% CI, 1.05‐1.10; P 3 positive nodes had a HR of 1.81 (95% CI, 1.12‐2.87; P = 0.014) and 2.51 (95% CI, 1.50‐4.24; P