SOMATOSTATIN ANALOG TREATMENT OF NEUROENDOCRINE TUMORS

The long-acting analogues of somatostatin have an established place in the medical treatment of patients with neuroendocrine tumours. They a ct through binding with specific, high-affinity membrane receptors. So matostatin analogue therapy is an effective and safe treatment for mos t growth hormone and thyrothropin-secreting pituitary adenomas. The po tential therapeutic consequences of the presence of somatostatin recep tors on clinically 'nonfunctioning' pituitary tumours are still uncert ain. Somatostatin analogues are not useful in the treatment of patient s with prolactinomas, or adrenocorticotropin (ACTH)-secreting adenomas . However, the somatostatin analogue octreotide suppressed pathologica l ACTH release in some patients with Nelson's syndrome and ACTH and co rtisol secretion in several patients with Gushing's syndrome caused by ectopic ACTH secretion. Somatostatin analogues are effective in the s ympatomatic treatment of most (metastatic) pancreatic islet cell tumou rs and most (metastatic) carcinoids. In some of these patients, they a lso induce tumour stabilisation or reduction. In some patients with (m etastatic) medullary thyroid carcinomas, continuous treatment with ver y high doses of octreotide can be of temporary relief. The clinical ef fectiveness of somatostatin analogues in patients with small cell lung cancer is currently under investigation. Long-term therapy with somat ostatin analogues of catecholamine-secreting (malignant) paraganglioma s and phaeochromocytomas has not shown clinical benefits.