THE DIAGNOSTIC UTILITY OF SOMATOSTATIN RECEPTOR SCINTIGRAPHY IN ONCOLOGY

Somatostatin receptor scintigraphy (SRS) with the diethylenetriaminope ntaacetic-acid-conjugated somatostatin analogue [In-111-DTPA-D-Phe(1)] octreotide, also known as In-111-pentetreotide, is a new non-invasive modality for the evaluation of tumours that express receptors for som atostatin. These receptors are present on neuroendocrine and other tum ours, including lymphomas and some breast cancers. In oncology SRS is a promising diagnostic tool for localizing primary tumours, staging, c ontrol and follow-up after therapy, and for identification of patients who may benefit from therapy with unlabelled octreotide or, in the fu ture, with radiolabelled octreotide. In the past few years many small and large studies investigating various aspects of SRS have been repor ted. In this review the value of SRS in the management of individual t umour types is explored. For many tumours the best sensitivity in lesi on detection is only achieved by very careful imaging after the admini stration of at least 200 MBq In-111-pentetreotide. On the basis of the current experience the main value of SRS in oncology is in the stagin g and evaluation of gastroenteropancreatic tumours, paragangliomas, sm all-cell lung cancer and lymphomas. Promising areas for SRS are the ev aluation of breast cancer, non-medullary thyroid cancer and melanoma, and initial results with targeted radionuclide therapy using radiolabe lled octreotide have been reported.