title: Predictive value of preablation stimulated thyroglobulin and thyroglobulin/thyroid-stimulating hormone ratio in differentiated thyroid cancer.
abstract: OBJECTIVE
  Recent studies have shown that thyroglobulin (Tg) concentration is a useful tumor marker in follow-up of differentiated thyroid cancer (DTC) patients after thyroidectomy and subsequent radioiodine (I-131) therapy. However, its role is controversial after total or near-total thyroidectomy before the first I-131 ablative treatment. So, we used thyroid-stimulating hormone (TSH) levels to normalize predictive values of Tg for DTC.
  
  
  METHODS
  The study was a retrospective analysis. A total of 244 patients with DTC who had undergone a total thyroidectomy and subsequent I-131 therapy were included. Exclusion criteria were patients with high serum Tg antibody (TgAb) concentration and in whom it was not measured. Patients were divided into 2 groups as M1 and M0, according to whether the patient present with or without distant metastases.
  
  
  RESULTS
  Preablative stimulated Tg in group M0 ranged between 0.1 and 348.9 ng/mL and group M1 between 0.2 and 1000 ng/mL. Tg/TSH ratios ranged 0.000667 to 12.143 ng/IU and 0.002948 to 12500 ng/IU. Both Tg and Tg/TSH values were significantly different between the 2 groups (the Wilcoxon rank sum test: Tg P < 0.0001 [z = 8.785]; Tg/TSH P < 0.0001 [z = 8.850]). The areas under receiver operating characteristic curves for Tg concentrations and Tg/TSH ratios were 0.913 and 0.916, respectively.
  
  
  CONCLUSIONS
  Both Tg and Tg/TSH ratios might be considered predictive markers for metastases of DTC just after total thyroidectomy before the first I-131 ablative therapy.
authors: Department of Nuclear Medicine, Chinese Academy of Medical Sciences, Beijing, China. linyansong68@yahoo.com.cn
authors: Yansong
authors: Y
authors: Lin
authors: Tianjun
authors: T
authors: Li
authors: Jun
authors: J
authors: Liang
authors: Xiaoyi
authors: X
authors: Li
authors: Liheng
authors: L
authors: Qiu
authors: Shasha
authors: S
authors: Wang
authors: Yonghui
authors: Y
authors: Chen
authors: Zengshou
authors: Z
authors: Kang
authors: Fang
authors: F
authors: Li
mesh_terms: D055011:Ablation Techniques; D000293:Adolescent; D000328:Adult; D000368:Aged; D002454:Cell Differentiation; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D013902:Radiography, Thoracic; D011877:Radionuclide Imaging; D013954:Thyroglobulin / Q000097:blood*; D013964:Thyroid Neoplasms / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D013972:Thyrotropin / Q000097:blood*; D051598:Whole Body Imaging
chemical_list: D007457:Iodine Radioisotopes; D013972:Thyrotropin; D013954:Thyroglobulin