REEVALUATION OF FALSE-POSITIVE FINDINGS O F SOMATOSTATIN-RECEPTOR SCINTIGRAPHY IN THE DIAGNOSIS OF NEUROENDOCRINE GASTROENTEROPANCREATIC TUMORS

Localization of gastroenteropancreatic neuroendocrine tumors with conv entional imaging techniques can be difficult. With the advent of the s omatostatin-receptor scintigraphy the diagnosis of these could be impr oved. In this study 76 patients with immunohistologically proven neuro endocrine tumors were analysed by comparing somatostatin-receptor scin tigraphy with conventional imaging techniques. Somatostatin-receptor-p ositive lesions were observed in 61 of all patients. Conventional imag ing techniques (transabdominal ultrasonography, computerized tomograph ic scanning of the abdomen, magnetic resonance imaging of the abdomen) revealed neuroendocrine tumors in 42 patients (69%). A follow up of 1 9 patients with initially false positive somatostatin-receptor scintig rams showed that at least 6 patients had escaped the initial diagnosis by conventional techniques. All in all, our data support previous fin dings and demonstrate that somatostatin-receptor scintigraphy is a saf e and sensitive procedure for in vivo imaging of gastroenteropancreati c neuroendocrine tumors. In addition, in certain cases, somatostatin-r eceptor scintigraphy is able to detect tumors that had escaped convent ional imaging techniques.