Epidemiological Trends For Functional Pancreatic Neuroendocrine Tumors: A Study Combining Multiple Imputation With Age Adjustment

Purpose: The purpose of this study was to examine trends in the incidence and incidence-based(IB)mortality of functional pancreatic neuroendocrine tumors(FPNETs),and to identify factors associated with survival times.Methods: Data were obtained from the Surveillance,Epidemiology,and End Results database from 2000 to 2017.Trends in the age-adjusted incidence of F-PNETs and IB mortality were examined using the Joinpoint Regression Program.Statistical analyses were run using chi-square tests,Kaplan–Meier curves,and the Cox proportional hazards model.Multiple imputation was used to deal with missing data.Results: A total of 142 patients with F-PNETs met the study inclusion criteria.It was found that the incidence of F-PNETs decreased over the study period,with an annual percent change(APC)of-2.5%(95% CI [-4.3,-0.5],P<0.05).This decrease was found to be significant for women,and also when limited to cases with distant disease or rare F-PNETs,with APCs of-4.2%(95% CI [-7.4,-0.9],P<0.05),-6.7%(95% CI [-10.4,-2.8],P<0.05),and-9.1%(95% CI [-13.5,-4.4],P<0.05),respectively.The Cox regression analysis revealed that the tumor size,tumor stage,tumor type,and surgical resection were associated with F-PNETs mortality.Conclusions: We found a continual decrease in the incidence of F-PNETs from 2000 to 2017.The prognosis and survival times were closely related to the calendar year at diagnosis,tumor stage,and tumor size.