Abstract
OBJECTIVE: This study aimed to describe the relative and excess risk of pancreatic neuroendocrine tumor (NET) at least 6 months after the first primary cancer (FPC) among the US population. METHODS: Surveillance, Epidemiology, and End-Results Program data were analyzed for patients diagnosed as having FPC from 2000 to 2015 (n = 4,008,092). Standardized incidence ratios, excess risk, and average time to diagnosis of a second primary pancreatic NET were reported by FPC site, stratified by sex and receipt of radiotherapy and chemotherapy. RESULTS: Risk of pancreatic NET was significantly higher after FPC at any site, any solid tumor (standardized incidence ratios, 1.3; 95% confidence interval, 1.2-1.5), pancreas, thymus, small intestine, liver, stomach, kidney, lung, and female breast. Excess incidence of pancreatic NET was highest among those with FPC (especially NET) of the pancreas, bladder, thymus, and female breast; those who received radiotherapy/chemotherapy for bladder, melanoma, and stomach cancers; and those who received chemotherapy for uterine, cervical, prostate, and other genital cancers. Time to diagnosis was shortest after pancreatic, liver, lung, and stomach cancer. CONCLUSIONS: Cancer survivors have increased risk and excess incidence of primary pancreatic NET compared with the population, particularly for certain primary sites. High-risk patients should receive regular follow-up screenings, counseling to reduce carcinogen exposure, and lifestyle interventions.