title: Somatostatin receptor scintigraphy in the follow-up of patients with differentiated thyroid cancer.
abstract: The aim of this study was to compare the results of somatostatin receptor scintigraphy (SRS) and of radioiodine scintigraphy in patients with metastatic differentiated thyroid carcinoma during L-thyroxine suppression therapy and after withdrawal. Twenty-five patients were studied: 16 patients had papillary cancer and 12 of them had metastatic disease; 9 patients had follicular cancer and 7 of these had known metastases. In 7 patients SRS was performed during thyroxine withdrawal, in 12 during thyroxine therapy within 9 months from radioiodine scintigraphy, in 6 others both during suppression therapy and after withdrawal. SRS was positive in 18 of 25 (72%) patients. It demonstrated lesions in 11 of 13 (85%) patients after thyroxine withdrawal and in 12 of 18 (67%) patients during thyroxine suppression. In 6 patients in whom a direct comparison was made before and after withdrawal, essentially the same information was obtained. Six of 8 (75%) patients with lesions that did not concentrate radioiodine showed uptake of labeled octreotide in these lesions. In 5 of 17 (29%) patients whose tumors concentrated radioiodine, no uptake was found during SRS.
  
  
  CONCLUSIONS
  1) in patients with metastatic differentiated thyroid carcinoma, tumor sites can be visualized using SRS; 2) there is no need to withdraw patients from suppression therapy in order to perform SRS; 3) in some patients whose lesions do concentrate labeled octreotide but not radioiodine, the use of somatostatin analogues labeled with (111)In or [90Y] can provide new therapeutic options.
authors: Department of Nuclear Medicine, University Hospital Rotterdam, The Netherlands.
authors: L M
authors: LM
authors: Haslinghuis
authors: E P
authors: EP
authors: Krenning
authors: W W
authors: WW
authors: De Herder
authors: A E
authors: AE
authors: Reijs
authors: D J
authors: DJ
authors: Kwekkeboom
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000000981:diagnostic imaging; D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging; D011877:Radionuclide Imaging; D017481:Receptors, Somatostatin / Q000032:analysis*; D013954:Thyroglobulin / Q000097:blood; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D007457:Iodine Radioisotopes; D017481:Receptors, Somatostatin; D013972:Thyrotropin; D013954:Thyroglobulin; D013974:Thyroxine