Scintigraphic assessment of pituitary adenomas and several diseases by indium-111-pentetreotide.

The aim of this study was to identify the specific somatostatin receptors expressed by several tumors, utilizing 111In-octreotide, a long acting somatostatin analogue. We studied two different groups of patients: the first group was composed of 21 patients suffering from different pituitary adenomas, while the second group consisted of 12 patients affected by several different neoplasms. In vivo scintigraphy showed pentetreotide receptors only in large GH-secreting adenomas and several macroadenomas. Concerning the endocrine activity of the adenomas, 111In-octreotide showed a good sensibility in detecting GH-secreting tumors. In the second group, 111In-octeotride proved to be a good diagnostic tool to show carcinoid lesions which were missed by other complementary methodologies.