A scintigraphic comparison of iodine-123-metaiodobenzylguanidine and an iodine-labeled somatostatin analog (Tyr-3-octreotide) in metastatic carcinoid tumors.
A number of neoplasms are known to express somatostatin receptors, and the use of somatostatin receptor imaging in their localization has recently been described. We compared an 123I-labeled somatostatin analog Tyr-3-octreotide (TOCT) and 123I-labeled metaiodobenzylguanidine (MIBG) scintigraphy in seven patients with histologically proven metastatic carcinoid tumors. The optimum time for identifying tumor uptake on scanning after [123I]MIBG was 24-48 hr, and after 123I-TOCT 10-30 min postinjection. Both radiopharmaceuticals showed a varying spectrum of tracer uptake ([123I]MIBG showed no uptake in one patient; minimal in two; moderate in two; and intense in two; 123I-TOCT showed no uptake in two patients; minimal uptake in one; moderate uptake in two; and intense uptake in two). In two patients, 123I-TOCT identified metastatic lesions not seen by [123I]MIBG scintigraphy. These preliminary results suggest that [123I]MIBG and 123I-TOCT are useful and complementary imaging techniques for detecting metastatic carcinoid tumors.
Bomanji
J
J
Department of Nuclear Medicine, St. Bartholomew's Hospital, London, United Kingdom.
Mather
S
S
Moyes
J
J
Ellison
D
D
Grossman
A
A
Britton
K E
KE
Besser
G M
GM
D019797:3-Iodobenzylguanidine; D000368:Aged; D002276:Carcinoid Tumor / Q000000981:diagnostic imaging / Q000556:secondary*; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000031:analogs & derivatives*; D011877:Radionuclide Imaging
D007457:Iodine Radioisotopes; D007462:Iodobenzenes; C045210:3-Tyr-octreotide; D019797:3-Iodobenzylguanidine; D015282:Octreotide