IN-111-PENTETREOTIDE DETECTION OF GASTRINOMA BEFORE AND AFTER SURGERY

Eighteen patients with Zollingel Ellison syndrome were studied with In -111-pentetreotide SPECT in order to localize gastinoma, the tumour re sponsible for this pathology. NMR imaging was also carried out. Eight patients were operated. In-111-pentetreotide was reinjected 4 hours be fore operation and the radioactivity of the excised tumours counted. T he nature of the withdrawn tissues was assessed by immunohistochemistr y (chromogranina A). The scintigraphy was repeated 3-6 months after su rgery. In-111 pentetreotide SPECT was more sensitive than NMR. It was also absolutely specific because all the radioactive rumours excised s howed positive chromogranin. A staining The radioactivity/gram counted in gastrinomas exceeded 10 fold the hepatic and biliary radioactivity and 20-100 folds the radioactivity of blood and omentum. In all the o perated patients but three, the scintigraphy performed after surgery d id not defect tumours. However complete eradication did not occur, bec ause though 3-6 months after surgery the gastrinemia was significantly lower with respect to pre-surgery results it did not return to normal values in all patients but two.