A rational approach to postoperative surveillance for resected non-functional pancreatic neuro-endocrine tumours

Abstract Background Non-functional pancreatic neuroendocrine tumours (NF-PNETs) are rare and have highly variable outcomes. Current guidelines recommend surveillance for NF-PNETs Methods Consecutive patients who underwent surgery for NF-PNETs between 2002 and 2015 were identified retrospectively. Data were collected on demographics, pre-operative laboratory results and histopathological tumour characteristics. Statistical analyses were based on penalised Cox-regression modelling and a decision-tree model. Comparison of the variables identified was performed using ROC curves to identify the most sensitive and specific variable associated with disease recurrence. Results We identified 73 patients (38 males) with a median age of 61.5 years (range: 31–79). The median period of follow-up was 49 months (5–131). During follow up, 10 deaths (13.9%) were recorded and disease recurrence occurred in 12 patients (16.4%). The Kaplan-Meier predicted 1-,3- and 5-year recurrence–free survival rates were 98.6% (95% CI = 95.9, 100%), 85.4% (76.9–94.8%) and 72% (58.7–88.2%) respectively. Cox multivariate analysis identified poor tumour differentiation (WHO G3 grade) and lymph node ratio (LNR) as independent predictors for recurrence (p  Conclusion Our results have identified a simple and sensitive criterion for risk stratifying post-resection surveillance. Prospective validation in larger patient cohort is now warranted.