O. Schillaci et al., SPECT IMPROVES ACCURACY OF SOMATOSTATIN RECEPTOR SCINTIGRAPHY IN ABDOMINAL CARCINOID-TUMORS, The Journal of nuclear medicine, 37(9), 1996, pp. 1452-1456
Abdominal carcinoid tumors are often small and difficult to localize.
Somatostatin receptors have been detected in carcinoids, thus enabling
their in vivo visualization by scintigraphy with In-111 pentetreotide
, a radiolabeled somatostatin analog. The aim of this study was to det
ermine the value of In-111-pentetreotide SPECT in the detection of abd
ominal carcinoids and to compare these results with the outcomes from
planar scans and conventional imaging techniques. Methods: Eighteen pa
tients with a present, or previously operated, abdominal carcinoid wer
e evaluated. Abdominal SPECT scans were acquired 4 hr postinjection of
In-111-pentetreotide and multiple planar views were performed at 4, 2
4, and 48 hr. Results: No adverse reactions were observed after radiop
harmaceutical injection. In 13 of 18 patients, abnormal sites of uptak
e were found by SPECT, which localized 9 abdominal extrahepatic lesion
s (in 7 patients) and 33 hepatic lesions (in 10 patients). No patholog
ic accumulation was seen in the five patients considered in complete r
emission after surgery. Planar scans visualized 5 abdominal extrahepat
ic sites (in 4 patients) and 21 liver tumor sites (in 7 patients), whi
le conventional procedures detected 3 abdominal extrahepatic lesions (
in 2 patients) and 30 hepatic lesions (in 7 patients). Conclusion: Ind
ium-111-pentetreotide scintigraphy is a safe and practical procedure.
SPECT appears to be more sensitive than planar scintigraphy and conven
tional methods to detect abdominal carcinoids: it can increase the num
ber of visualized tumor sites and that of patients with positive findi
ngs and may therefore have a role not only in the mapping of tumor spr
ead but also in therapeutic decisions.