Diagnostic features and management options for duodenal neuroendocrine neoplasms: a retrospective, multi-centre study

Duodenal neuroendocrine neoplasms (dNENs) are rare neoplasms but their incidence is on the rise. They are classified into 5 sub-types but there remains much heterogeneity in behaviour in particular of non-functioning dNENs. To retrospectively analyse outcomes for all types of dNENs, and highlight prognostic factors associated with worse outcome. 102 (57 m/45f.) patients were identified with mean age at diagnosis 62 (range 32-87) years. The majority were non-functioning tumours 87/102 and median size was 10 mm (range 0.9-130 mm). 83 patients had Stage I or II disease, of which 17 underwent endoscopic resection with R1 rate of 45% and complication rate 12%. 36 patients were kept under endoscopic surveillance. There were 11 deaths of which 4 were disease related. Age and Ki67 > 20% were associated with worse OS in all dNENs. In non-functioning dNENs Ki67 > 3% was a predictor of lymph nodes metastases with OR 18.2 (2.54-13) (p < 0.005) in univariate analyses and liver metastases with OR 6.79 (1.56-29.5) (p < 0.05) in the multivariate analysis. Lesions 11-20 mm in size had OR 11.1 (1.16-106) compared to lesions < 11 mm for the prediction of lymph node metastases in the multivariate analysis (p < 0.05). ROC analysis of size of non-functioning dNENs to predict LN metastases found < 15 mm had an AUROC of 0.9 (0.81-0.99) with a sensitivity of 85% and specificity of 88%. dNENs are increasing in incidence, however low grade and smaller lesions have an indolent course and the role of endoscopic resection and active surveillance needs to be reviewed.

Automated summary

Duodenal neuroendocrine neoplasms (dNENs) are rare neoplasms but their incidence is increasing. Age and Ki67 levels are associated with worse prognosis in dNENs. Ki67 > 3% is a predictor of lymph nodes and liver metastases in non-functioning dNENs. Lesions 11-20 mm in size have a higher prediction of lymph node metastases. Non-functioning dNENs smaller than 15 mm have a high sensitivity in predicting lymph node metastases.