SINGLE-PHOTON EMISSION COMPUTERIZED-TOMOGRAPHY INCREASES THE SENSITIVITY OF INDIUM-111-PENTETREOTIDE SCINTIGRAPHY IN DETECTING ABDOMINAL CARCINOIDS

Somatostatin (sms) receptors have been identified in carcinoids (c), s o enabling their visualization with pentetreotide scintigraphy. The ai m of this study was to evaluate if single photon emission computerized tomography (SPECT) can increase the sensitivity of sms receptor scint igraphy in the detection of abdominal c. 26 patients (pts) with a pres ent, or previously operated, abdominal carcinoid were submitted to SPE CT over the abdomen and multiple planar views after the injection of I n-111-pentetreotide. Magnetic resonance imaging and computed tomograph y were also performed. In 19 pts abnormal sites of uptake were found b y SPECT which localized 13 abdominal extrahepatic (in 11 pts) and 45 h epatic lesions (in 15 pts). No pathologic accumulation was seen in 7 p ts in complete remission after surgery. Planar images visualized 7 abd ominal extrahepatic (in 6 pts) and 26 liver tumor sites (in 10 pts), c onventional procedures detected 5 abdominal extrahepatic (in 4 pts) an d 36 hepatic lesions (in 10 pts). In-111-pentetreotide SPECT is more s ensitive than planar scanning and conventional methods to detect abdom inal c, and so may play a major role in the early and accurate mapping of tumour spread.