Glucagonomas, VIPomas and somatostatinomas.

The three new endocrine pancreatic tumour syndromes dealt with in this chapter--glucagonomas, VIPomas and somatostatinomas--are not common. Nonetheless, the patients are potentially curable by tumour resection and therefore wider knowledge of the clinical picture is of considerable importance. It is possible that there are still further, presently unrecognized, clinical syndromes waiting in the wings and studies are currently under way to try to ascertain the effects of elevated PP. Early tumour diagnosis depends firstly on clinical acumen but the easy availability of a reliable radioimmunoassay service is of considerable importance as this allows the physician to screen likely patients and so detect cases at an early stage. Tumour localization is still a major problem and requires expert radiological assistance. The dramatic effectiveness of the cytotoxic agent streptozotocin illustrates the great potential of chemotherapy and it may be expected that further drugs of this nature will be discovered, especially as it is now possible to establish isolated tumour strains for mass drug screening. These tumours have shown the effect of long continued peptide elevation and given valuable insight into the physiological role of the respective regulatory peptides.