Incidence, survival, and prognostic nomogram of patients with small intestinal neuroendocrine tumors: A SEER population-based study

Small intestinal neuroendocrine tumors (SI-NETs) are a group of rare and significantly heterogeneous tumors with limited research currently available. This study aimed to investigate the incidence, survival, and prognostic factors of SI-NETs. We selected data from the surveillance, epidemiology, and end results (SEER) database between 2000 and 2019 and evaluated the incidence trend of SI-NETs during this period. We utilized the Kaplan-Meier method to examine the association between clinical variables and survival rates. Based on the multivariable Cox regression analysis results, we developed a nomogram to predict the 1-, 2-, and 3-year cancer-specific survival (CSS) of SI-NETs patients. We evaluated the consistency, accuracy, and clinical utility of the nomogram by drawing calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA) curves. The incidence of SI-NETs showed an upward trend in recent years. Age, grade, T stage, M stage, and primary tumor surgery were independent risk factors for CSS in SI-NETs patients. The nomogram model based on these risk factors showed high accuracy and clinical benefit. SI-NETs are rare tumors with an increasing incidence rate. The nomogram model is expected to be an effective tool for personalized prognosis prediction in SI-NETs patients, which may benefit clinical decision-making.