Incidence, Clinical Presentation and Trends in Indication for Diagnostic Work-Up of Small Intestinal and Pancreatic Neuroendocrine Tumors

Abstract

Background: The incidence of small intestinal (SI) and pancreatic neuroendocrine tumors (siNETs and pNETs) seems to have increased. The increased frequency of incidental findings might be a possible explanation. The study aimed to examine (1) changes in incidence and the stage at diagnosis (2010–2011 vs. 2019–2020), (2) changes in the initial indication for diagnostic workup and 3) the differences in stage between incidentally discovered vs. symptomatic disease during the entire study period. Methods: We performed a retrospective study, that includes consecutive siNET and pNET patients referred to the Copenhagen ENETS center of excellence in 2010–2011 and 2019–2020. Results: The annual incidence of siNET per 100,000 increased from 1.39 to 1.84, (p = 0.05). There was no change in the stage at diagnosis, and in both periods approximately 30% of patients were incidentally diagnosed (p = 0.62). Dissemination was found in 72/121 (60%) of symptomatic vs. 22/50 (44%) of incidentally discovered SI tumors in the entire cohort, (p = 0.06). The annual incidence of pNET increased from 0.42 to 1.39 per 100,000, (p < 0.001). The proportion of patients with disseminated disease decreased from 8/21 (38%) to 12/75 (16%), (p = 0.02) and the number of incidental findings increased from 4/21 (19%) to 43/75 (57%), (p = 0.002). More symptomatic patients had disseminated disease compared to patients with incidentally discovered tumors (15/49 (31%) vs. 5/47 (11%), (p = 0.01)). Conclusion: The incidence of siNET and pNETs increased over the past decade. For siNETs, the stage of disease and the distribution of symptomatic vs. incidentally discovered tumors were unchanged between the two periods. Patients with pNETs presented with more local and incidentally discovered tumors in the latter period. Patients with incidentally discovered siNETs had disseminated disease in 44% of the overall cases. The vast majority of incidentally found pNETs were localized.

Outlook for 615 Small Intestinal Neuroendocrine Tumor Patients: Recurrence Risk after Surgery and Disease-Specific Survival in Advanced Disease

“…As one hypothesis, the rise in incidence has been attributed to improved and more frequent use of imaging, leading to incidental discoveries of siNET. However, we have previously shown that the proportion of patients incidentally diagnosed in 2010–2011 vs. 2019–2020 was unchanged in our center [ 36 ]. Thus, there may be a genuine increase in siNET incidence together with other contributing factors such as increased awareness among pathologists and clinicians.…”

Recurrence-Free Survival and Disease-Specific Survival in Patients with Pancreatic Neuroendocrine Neoplasms: A Single-Center Retrospective Study of 413 Patients

“…The majority of pancreatic NENs (pNENs) are well-differentiated non-functioning tumors [ 2 , 3 , 4 ]. During the last 50 years, numerous studies have documented a significant increase in the incidence of pNEN [ 5 , 6 , 7 ]. A possible explanation for this rise includes an increased number of incidentally discovered tumors, greater awareness among pathologists, and a true increase in incidence [ 6 ].…”

A New Preoperative Scoring System for Predicting Aggressiveness of Non-Functioning Pancreatic Neuroendocrine Neoplasms

“…Pancreatic neuroendocrine neoplasms (PanNENs) are rare pancreatic tumors, accounting for 1–2% of all pancreatic tumors [ 1 , 2 , 3 ]. The number of PanNENs cases is steadily increasing [ 4 , 5 , 6 ]. The Surveillance, Epidemiology, and End Results (SEER) database revealed that the annual incidence of patients with PanNENs in the USA were 0.27 per 100,000 in the period 1987–1996, 0.43 in 1997–2006, and 1.01 in 2007–2016 [ 3 ].…”

“…The Surveillance, Epidemiology, and End Results (SEER) database revealed that the annual incidence of patients with PanNENs in the USA were 0.27 per 100,000 in the period 1987–1996, 0.43 in 1997–2006, and 1.01 in 2007–2016 [ 3 ]. The incease is particularly evident in asymptomatic and small non-functioning PanNENs (NF-PanNENs) [ 4 , 5 , 6 ]. According to a population-based study based in the USA, the incidence of pancreatic neuroendocrine tumors (PanNETs) ≤ 2 cm increased by 710% between 1988 and 2012 [ 4 ].…”

“…According to a population-based study based in the USA, the incidence of pancreatic neuroendocrine tumors (PanNETs) ≤ 2 cm increased by 710% between 1988 and 2012 [ 4 ]. The proportion of the incidentally-detected cases increased from 19% of all NF-PanNENs cases in the period 2010–2011 to 57% in 2019–2020 [ 6 ]. These increases are likely to be attributable to the advances in imaging modalities, including endoscopic ultrasonography (EUS) [ 4 , 7 ].…”