Abstract
The incidence of neuroendocrine neoplasms (NENs) is increasing, especially for patients with early stages and grade 1 tumours. Current evidence also shows increased prevalence, probably reflecting earlier stage diagnosis and improvement of treatment options. Definition of adequate postsurgical follow-up for NENs is a current challenge. There are limited guidelines, and heterogeneity in adherence to those available is notable. Unfortunately, the population of patients at greatest risk of recurrence has not been defined clearly. Some studies support that for patients with pancreatic neuroendocrine tumours (PanNETs), factors such as primary tumour (T), stage, grade (Ki-67), tumour size, and lymph node metastases (N) are of relevance. For bronchial neuroendocrine tumours (LungNETs) and small intestinal neuroendocrine tumours (siNETs), similar factors have been identified. This review summarises the evidence supporting the rationale behind follow-up after curative resection in well-differentiated PanNETs, siNETs, and LungNETS. Published evidence informing relapse rate, disease-free survival, and relapse patterns are discussed, together with an overview of current guidelines informing postsurgical investigations and duration of follow-up.
Highlights
Neuroendocrine neoplasms (NENs) are rare and heterogeneous [1,2]
This review summarises the available evidence supporting follow-up after curative resection of sporadic well-differentiated NETs arising from the pancreas (PanNETs), small intestine, and lung (LungNETS)
PanNETs, well-differentiated pancreatic neuroendocrine tumours; siNETs, well-differentiated small intestinal neuroendocrine tumours; LungNETs, well-differentiated lung carcinoids; Chromogranin A (CgA), chromogranin A; 5-HIAA, 5-hydroxyindoleacetic acid; NSE, neuron-specific enolase; CT, computerised tomography; MRI, magnetic resonance imaging; SSTR, somatostatin receptor; PET, positron-emission tomography; 18F-FDG, fluorodeoxyglucose; 68Ga-DOTA, 68Ga-dodecanetetraacetic acid. ** According to the ENETS guidelines, follow-up with SSTR imaging if positive at diagnosis could be considered. # According to the ENETS guidelines, follow-up with 18F-FDG PET, if positive at diagnosis could be considered for atypical
Summary
Neuroendocrine neoplasms (NENs) are rare and heterogeneous [1,2]. Assessment of stage, primary tumour site, and tumour grade are the cornerstones for treatment planning [3,4]. For gastro-entero-pancreatic (GEP)-NENs, the World Health Organisation (WHO) tumour grade is defined by the percentage of tumour cells with a nuclear expression of Ki-67 and morphological differentiation features (well-differentiated (called neuroendocrine tumour (NET)) vs poorly-differentiated (called neuroendocrine carcinoma (NEC))) [5,6,7]. This review summarises the available evidence supporting follow-up after curative resection of sporadic (nonhereditary) well-differentiated NETs arising from the pancreas (PanNETs), small intestine (excluding appendix) (siNETs), and lung (LungNETS). This manuscript reviews current guidelines and identifies areas of uncertainty to be addressed by future research. This manuscript will not cover specific recommendations for NETs arising from the appendix or rectum
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call