Somatostatin receptors are activated by somatostatin secreted from nerve and endocrine cells. The Somatostatin Receptors (SSTRs) are expressed in a tissue-specific manner and involved in the regulation of secretion of insulin, glucagon and growth hormone as well as cell growth induced by neuronal excitation in both the central and peripheral nervous systems. Aberrent expression of somatostatin receptors is known in a large number of human tumours. SSTR2 is expressed in highest levels in the stomach, jejunum, cerebrum, thyroid and kidney. Its gene expression is lost in 90% of human pancreatic adenocarcinomas while SSTR2 expression in neuroblastoma correlates positively to overall and event-free survival. Expression of SSTR-2 and SSTR-5 may be important in the growth inhibitory effect of somatostatin in human pancreatic cancer.