Somatostatin and the lung.

Lung carcinoma is the most common cause of death in the western world and is increasing particularly among women. Despite significant developments in our understanding of the molecular biology of this disease our ability to treat the various subtypes of lung cancer has been at a relative standstill for the past decade. Novel approaches to the therapy of lung tumours are required. Recent work has evaluated the potential role of somatostatin and its analogues in the treatment of lung cancer. Experimental evidence has demonstrated that lung tumours, in particular small cell lung cancer (SCLC), may express somatostatin. The significance of this expression has not yet been evaluated. Somatostatin receptors have been demonstrated on between 50-75% of SCLC cell lines and fresh tumour samples studied to date. Using radiolabelled somatostatin analogues SCLC tumours may be detected and localised in patients through scintigraphic imaging techniques. Studies have shown that SCLC cell line clonal proliferation may be inhibited in vitro with somatostatin analogues suggesting that the somatostatin receptors are functional. In-vivo growth inhibition studies have likewise yielded encouraging results with growth inhibition of somatostatin receptor positive SCLC xenografts and receptor negative SCLC and non-small cell lung cancer cell line xenografts. These latter result suggests that somatostatin analogues may inhibit tumour growth by indirect as well as direct means. These findings have laid the ground for formal clinical trials in the future.