Neuroendocrine tumours are relatively rare tumours however the incidence has increased over the last 20 years from approximately 2 per 100,000 to 4 per 100,000 per year. These tumours are derived from the diffuse endocrine system and can be found anywhere in the body. They are classified according to their site of origin and whether they are functioning (hormone secreting) or non-functioning (non-hormone secreting). There are many types of neuroendocrine tumours including: medullary thyroid cancers, paragangliomas, phaeochromoctomas, bronchial carcinoids and the most common gastroenteropancreatic (GEP) tumours which encompass pancreatic islet cell tumours (e.g. insulinoma, gastrinoma, VIPoma, glucagonoma and non-functional tumours) as well as gastrointestinal carcinoid tumours originating in the foregut, midgut or hindgut.
For the optimal management of NETs, the following strategy has been suggested:(i) suspect the diagnosis; (ii) perform appropriate biochemistry profile including urine 24 hour 5 hydroxyindole acetic acid (5HIAA) and serum hormone including chomogranin A measurements; (iii) assessment of histopathology to confirm diagnosis and determine aggressiveness of the disease e.g. features of tumour differentiation, invasion and proliferation index; (iv) determine the presence of inherited disorder such as Multiple Endocrine Neoplasia type 1 (MEN-1) or the Von Hippel-Lindau syndrome; (v) determine the site and extent of disease using for example contrast CT or MRI, as well as the most sensitive modality the Indium-111 Octreotide scan; (vi) treat the symptoms or excessive hormonal state; (vii) treat the disease if possible with curative surgery otherwise consider surgical debulking. Non-surgical treatments of metastatic disease (including somatostatin analogues, interferon alpha, chemotherapy, hepatic artery embolization and radionuclide therapies such as I-131 MIBG and Yttrium-90 DOTA Octreotide); and (viii) all patients will require long term follow-up preferably within treatment protocols.
The management options are many and with little evidence based practice controlled studies and formal guidelines are required and are in progress.
01 - 03 Nov 2004
Society for Endocrinology