Treatment of neuroendocrine GEP tumours with somatostatin analogues - A review

Background: Somatostatin and its long-acting analogues are effective in sym ptom control in patients with functionally active neuroendocrine GEP tumour s. Several in vitro and in vivo reports suggest that they are also able to control tumour growth. Methods: Critical review of published data on the ef fect of long-acting somatostatin analogues on symptom and growth control in patients with metastatic neuroendocrine GEP tumours. Results: With the exc eption of insulinoma and gastrinoma, octreotide acetate and other long-acti ng somatostatin formulations are currently the therapeutic principle of fir st choice to control hormone-mediated symptoms. The consequences of gastric acid hypersecretion in patients with Zollinger-Ellison syndrome are best c ontrolled by proton pump inhibitors. Available data on growth control indic ate that stabilization of tumour growth seems to be the most beneficial ant iproliferative effect occurring in up to 50% of patients, This effect is li mited. However, it is unknown which tumour entity responds best to long-act ing somatostatin analogues, Conclusion: Additional studies in patients with known spontaneous tumour growth and avoiding a mix-up of different entitie s of neuroendocrine malignancies are necessary to identify subpopulations o f neuroendocrine tumours which respond to long-acting somatostatin analogue s in terms of longer lasting growth inhibition, Copyright (C) 2000 S. Karge r AG, Basel.