Chemotherapy and biotherapy in the treatment of neuroendocrine tumours

The medical treatment of neuroendocrine GEP tumours must be based on the gr owth properties of the tumour. Medical treatment includes chemotherapy, som atostatin analogues and alpha interferons. Chemotherapy has been particular ly active in patients with high proliferating neuroendocrine tumours such a s endocrine pancreatic tumours and lung carcinoids. Streptozotocin-based co mbinations including 5-flourouracil and doxorubicin have generated partial remissions in 40%-60% of the patients giving a median survival of about two years in patients with advanced disease. Cisplatinum plus etoposide have d emonstrated significant antitumour effects in anaplastic endocrine pancreat ic tumours and lung carcinoids. However, in low proliferating tumours such as classical midgut carcinoids the response rates with the same combination s of cytotoxic agents have only generated short lasting responses in less t han 10% of patients. In these patients, biological treatment has been of be nefit. Alpha interferon at doses of 3-9 million units three to seven times per week subcutaneously, has given biochemical response rates of 50% and si gnificant tumour reduction in about 15% of patients with Iona duration, up to three years. Somatostatin analogues have been widely used in the treatment of neuroendoc rine gut and pancreatic tumours. The currently available somatostatin analo gues particularly bind somatostatin receptor 2 and 5 and with low affinity also receptor subtype 3. Octreotide is registered in most countries for the treatment of patients with carcinoid syndrome and also VIP and glucagon pr oducing tumours. Regular octreotide at standard doses of 100-300 mug/day gi ves symptomatic responses in a medium of 60% of patients and biochemical re sponses in up to 70% of patients. Significant tumour responses are rare, le ss than 5%. Long-acting formulations of somatostatin analogues have been of significant benefit for the patients with similar response rates as for re gular formulations. The quality of life has been significantly improved by using the long-acting formulations.