Neuroendocrine Tumours in the Gastrointestinal Tract: What You Need to Know

Neuroendocrine neoplasms (NENs) comprise well differentiated neuroendocrine tumours (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). NENs can develop at various anatomical sites, the most common being in the gastrointestinal tract and their incidence is increasing. Although uncommon, they are no longer considered to be rare. Comprehensive biochemical, histopathological and imaging investigations are required to assess an NEN's site, grade and stage and to determine whether it is producing hormones and resulting in a hormonal syndrome. Localised NENs are typically managed with surgery, while metastatic NENs are often treated initially with systemic therapy, such as somatostatin analogue injections. There are multiple options for NEN management, so these patients need to be discussed and managed by a multidisciplinary team of clinicians who have expertise in this tumour type. This article is intended to provide an introduction and summary for clinicians who have little prior experience of NENs.