Carcinoids may express Somatostatin receptors. Therefore, a Somatostatin-analogue, In-111 Octreotide (OctreoScan), was used for their demonstration. A total of 6 patients who presented with radiologically verified carcinoid-metastases was examined. In order to control tumor progress, 4 of these patients were reexamined within a period of 3 to 11 months. All of the radiological findings were confirmed scintigraphically, except some small retroperitoneally located lymph nodes. The follow-up examinations of 2 patients revealed additional metastases by scintigraphy only. There were no false positive results. The results of OctreoScan scintigraphy may be used for predicting the success of receptor-specific therapies and therefore, permit the rational and efficient application of Sandostatin.