Prognosis after curative resection of non-metastatic pancreatic neuroendocrine tumors: a retrospective tertiary center study

Background: Pancreatic neuroendocrine tumors (pNETs) are rare tumors with heterogeneous outcomes. The aim of our study was to determine the long-term outcome, recurrence patterns, as well as the clinical and pathological factors that impact time-to-recurrence (TTR), recurrence-free survival (RFS), and overall survival (OS) in pNETs treated with curative surgery.

Methods: Data for all patients who underwent radical surgery with curative intent for non-metastatic pNETs were obtained from a prospectively maintained database of the University Hospitals Leuven. Data from September 2002 until November 2021 were analyzed retrospectively. Patients with metastatic disease and/or neuro-endocrine carcinoma were excluded. Median follow-up time was calculated using the reverse Kaplan-Meier method. A Cox proportional hazards model was used to assess variables associated with recurrence.

Results: The study included 128 patients. Only 8 patients (6.3%) had recurrent disease over a median follow up of 44.4 months (interquartile range [IQR] 29.8-74.7). The median TTR was 38.7 months (IQR 18.0-46.2). Univariate analysis showed that multiple endocrine neoplasia type 1 (MEN-1) and R1-status were statistically significant predictors for disease recurrence.

Conclusions: In our series of patients treated with surgery for non-metastatic, well-differentiated pNETs, recurrence was low at 6.3%. MEN-1 and R1-status were predictors for recurrence in univariate analysis.