title: Expression of the sodium iodide symporter in differentiated thyroid cancer: clinical evidence.
abstract: OBJECTIVE
  Molecular analysis of the expression of the sodium iodide symporter (NIS) in 32 patients with differentiated thyroid cancer (DTC) and correlation with scintigraphic findings ((131)I,(123)I) in 19 (59.4%) of them.
  
  
  METHODS
  NIS expression of 27 primary tumours, 13 lymphnodes and 18 distant metastases was determined by immunostaining using a murine monoclonal anti-NIS-antibody. NIS expression and radionuclide uptake of metastases were analysed by a semiquantitative visual score. Patients were divided into two subgroups: Group 1 (n = 8 patients): indirect correlation of radioiodine uptake (RIU) of subsequent metastases with NIS expression of 7 primary tumours and 3 metastases; Group 2 (n=11 patients): direct correlation of radionuclide uptake with NIS expression of 19 metastases which were excised after imaging.
  
  
  RESULTS
  49 of 58 specimens (84.5%) were NIS-positive. A preserved NIS-expression was found in 12 primary tumours and 8 of 10 (80%) synchrone and 6 of 7 (85.7%) metachrone metastases. Group 1 revealed a 100% positive predictive value (PPV) of a preserved NIS expression in the primary tumour regarding radioiodine uptake in metastases while a lack of NIS expression in the primary tumor did not reliable predict a loss of the metastases' ability to concentrate radioiodine. In group 2, only 11 of 19 (57.9%) specimens showed a concordant NIS expression and RIU whereas in the remaining 8 cases without visible RIU NIS expression was still present.
  
  
  CONCLUSIONS
  NIS expression of the primary tumour and metastases in DTC is usually well preserved. We found a positive correlation between NIS expression of the primary and metastatic tissue but could not identify such well correspondence between NIS expression and the RIU of subsequent metastases.
authors.affiliation: Department of Nuclear Medicine, Georg August University, Robert-Koch-Str. 40, 37075 Göttingen, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Schmitz
authors.forename: L
authors.initials: L
authors.lastname: Füzesi
authors.forename: J
authors.initials: J
authors.lastname: Struck
authors.forename: U
authors.initials: U
authors.lastname: Siefker
authors.forename: A
authors.initials: A
authors.lastname: Hamann
authors.forename: C-O
authors.initials: CO
authors.lastname: Sahlmann
authors.forename: M
authors.initials: M
authors.lastname: Hüfner
authors.forename: J
authors.initials: J
authors.lastname: Meller
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D027981:Symporters / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D013972:Thyrotropin / Q000097:blood; D000099209:Sodium-Iodide Symporters
chemical_list: D019788:Fluorodeoxyglucose F18; D019275:Radiopharmaceuticals; D027981:Symporters; D013972:Thyrotropin; D000099209:Sodium-Iodide Symporters