Survival Trends in Patients with Small Intestinal Neuroendocrine Tumours—A Cohort Study in Central Norway

Abstract

Improved surgical resection and oncological treatment, or an earlier diagnosis may increase survival in small intestinal neuroendocrine tumours (SI-NETs), but only few studies have examined survival trends. We aimed to examine the trend in overall survival and associated factors in SI-NET patients. All patients with SI-NETs at a regional hospital from June 2005 to December 2021 (n = 242) were identified, and the cohort was divided in half, constituting a first period (until November 2012) and a second period (from November 2012). Disease and treatment characteristics, including European Neuroendocrine Tumour Society (ENETS) stage, surgery, oncological treatment and survival, were recorded. The majority (n = 205 (84.7%)) were treated surgically and surgery was considered curative in 137 (66.8%) patients. Median survival was longer in the second period (9.0 years 95% CI 6.4–11.7 in the first period vs. median not reached in the second period, p = 0.014), with 5-year survival rates of 63.5% and 83.5%, respectively. ENETS stage and oncological treatment did not differ between the periods, but factors associated with surgical quality, such as lymph node harvest and resection of multiple SI-NETs, were significantly higher in the second period. Age, ENETS stage, time period and tumour resection were independently associated with survival in a multivariate analysis.