Gut hormone secreting tumours.

Gut peptide secreting tumours originate most commonly from the pancreatic Islets of Langerhans. Tumours at a variety of other sites have also been shown to synthesize and release these peptides, reflecting the wide distribution of the peptide secreting cells of the diffuse neuroendocrine system. Tumours such as the glucagonomas, insulinomas, VIPomas and gastrinomas are associated with characteristic clinical syndromes resulting from the effects of the peptide they secrete. The majority of the islet cell tumours in fact secrete a number of different peptides and many of these are present in several molecular forms, some of which may not be biologically active. This may explain the lack of clinical sequelae in association with tumours such as the somatostatinomas. The clinical features, methods of diagnosis, localisation and treatment of these tumours will be discussed.