Incidence and survival of patients with malignant pancreatic neuroendocrine neoplasms in Germany, 2009-2021.

Abstract

<h4>Background</h4>Due to the rarity of pancreatic neuroendocrine neoplasms, only few population-representative studies on incidence and survival have been conducted. The aim was to provide up-to-date nationwide incidence and relative survival estimates of neuroendocrine (NE) neoplasms overall, NE tumors (NETs), NE carcinomas (NECs), and mixed NE neoplasms (MiNEN).<h4>Methods</h4>We distinguished between pancreatic NETs (functioning versus non-functioning), NECs and mixed NE neoplasms and analyzed data from 2009 through 2021 from all German cancer registries covering a population of more than 80 million. We calculated crude and age-standardized incidence rates and 5-year relative survival estimates (RS).<h4>Results</h4>Overall 6474, 4217, and 243 patients with pancreatic NETs, NECs, and mixed NE neoplasms, respectively were registered. While the age-standardized incidence of NETs has increased (+16.4 % per year, 95 %CI 12.2;20.7), the incidence of NEC has fallen (about -6.4 % per year, 95 %CI -8.0; -4.8). The crude RS was 77.7 % (standard error [SE] 0.9) for non-functioning NETs, 90.3 % for functioning NETs (SE 3.9), and 18.5 % (SE 3.9) for MiNEN. Large and small cell NECs had a low RS (9.1 % and 6.9 %, respectively). RS for G1 NETs was 88.2 %, while it was only 36.6 % for G3 NETs. Localized NETs had a RS of 92.8 %, while distant metastatic NETs had a RS of 45.0 %.<h4>Conclusions</h4>The incidence of pancreatic NETs has increased markedly in Germany in the period 2009-2021. Subgroups of NETs (G1 grading or localized stage) have an excellent prognosis. RS of MiNEN is more similar to NECs than NETs.