Added value of gastrin receptor scintigraphy in comparison to somatostatin receptor scintigraphy in patients with carcinoids and other neuroendocrine tumours.
Gastrin receptor scintigraphy (GRS) is a new imaging method primarily developed for the detection of metastases of medullary thyroid carcinoma (MTC). As gastrin-binding CCK(2) receptors are also expressed on a variety of other neuroendocrine tumours (NET), we compared GRS to somatostatin receptor scintigraphy (SRS) in patients with NET. SRS and GRS were performed within 21 days in a series of 60 consecutive patients with NET. GRS was directly compared with SRS. If lesions were visible on GRS but not detectable by SRS, other imaging modalities (MRI, CT) and follow-up were used for verification. Of the 60 evaluable patients, 51 had carcinoid tumours, 3 gastrinomas, 2 glucagonomas, 1 insulinoma and 3 paragangliomas. The overall tumour-detection rate was 73.7% for GRS and 82.1% for SRS. In the 11 patients with negative SRS, GRS was positive in 6 (54.5%). Based on the number of tumour sites detected and the degree of uptake, GRS performed better than SRS in 13 patients (21.7%), equivalent images were obtained in 18 cases (30.0%) and SRS performed better in 24 (40.0%) cases. In six of the SRS positive patients, 18 additional sites of tumour involvement could be detected. Overall, GRS detected additional tumour sites in 20% of the patients. Localisation of the primary tumours or their functional status had no influence on the outcome of imaging. GRS should be performed in selected patients as it may provide additional information in patients with NET with equivocal or absent somatostatin uptake.
Gotthardt
Martin
M
Department of Nuclear Medicine, Radboud University Nijmegen Medical Center, Postbus 9101, 6500 HB Nijmegen, The Netherlands. m.gotthardt@nucmed.umcn.nl
Béhé
Martin P
MP
Grass
Julia
J
Bauhofer
Artur
A
Rinke
Anja
A
Schipper
Meike L
ML
Kalinowski
Marc
M
Arnold
Rudolf
R
Oyen
Wim J G
WJ
Behr
Thomas M
TM
D000328:Adult; D000368:Aged; D002276:Carcinoid Tumor / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005260:Female; D005935:Glucagonoma / Q000000981:diagnostic imaging; D006801:Humans; D007205:Indium Radioisotopes; D007340:Insulinoma / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000378:metabolism; D015282:Octreotide / Q000031:analogs & derivatives; D010235:Paraganglioma / Q000000981:diagnostic imaging; D004369:Pentetic Acid / Q000031:analogs & derivatives; D011379:Prognosis; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D043887:Receptor, Cholecystokinin B / Q000378:metabolism*; D017481:Receptors, Somatostatin / Q000378:metabolism*
D007205:Indium Radioisotopes; D019275:Radiopharmaceuticals; D043887:Receptor, Cholecystokinin B; D017481:Receptors, Somatostatin; C071632:SDZ 215-811; D004369:Pentetic Acid; D015282:Octreotide