title: Significance of postoperative serum thyroglobulin levels in patients with papillary and follicular thyroid carcinomas.
abstract: OBJECTIVE
  Although there are many factors that affect postoperative serum levels of thyroglobulin (Tg), such levels have been previously used to detect recurrence of papillary and follicular thyroid carcinomas. This study was conducted to elucidate the significance of postoperative levels of Tg in patients with clinical presentations of papillary thyroid carcinoma, follicular thyroid carcinomas, or both.
  
  
  METHODS
  To collect data pertaining to patients with thyroid cancer who were treated in Chang Gung Medical Center in Linkou, Taiwan, records relating to a total of 847 patients with pathologically verified papillary or follicular thyroid cancer, all of whom received total thyroidectomy and thyroid remnant ablation with radioactive iodide ((131)I), were studied. To evaluate the clinical significance of postoperative levels of Tg, the patients were categorized into three groups based on postoperative Tg level. Group A was classified as those demonstrating a 1-month postoperative Tg levels less than 1 ng/ml. Group B patients were classified as those displaying a 1-month postoperative Tg levels greater than or equal to 1 ng/ml, but less than 10 ng/ml. Group C patients were classified as those exhibiting a 1-month postoperative Tg levels great than or equal to 10 ng/ml.
  
  
  RESULTS
  Of the patients in group A, none presented with distant metastases at the time of diagnosis or during the follow-up period. In group B, 15 patients (3.5%) died of thyroid cancer. In this group, tumor size was an important factor in cancer-related mortality, diagnostic clinical class, and follow-up status. Of the 491 patients in group C, 49 (10.0%) patients died of thyroid cancer. Among the patients in group C, age, histopathologic type, stage of diagnosis, and follow-up Tg values were important factors. Among groups A, B, and C, there were 161 (95.8%), 253 (76.4%), and 129 (37.1%) patients, respectively, with disease-free status at the end of 1998.
  
  
  CONCLUSIONS
  Postoperative serum Tg levels can be used as a prognostic indicator in patients with papillary and follicular thyroid cancer. For patients with Tg levels greater than or equal to 10 ng/ml, Tg levels are a useful marker to predict prognosis.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University, Taiwan, Republic of China. einjd@adm.cgmh.com.tw
authors.forename: Jen-Der
authors.initials: JD
authors.lastname: Lin
authors.forename: Miau-Ju
authors.initials: MJ
authors.lastname: Huang
authors.forename: Brend Ray-Sea
authors.initials: BR
authors.lastname: Hsu
authors.forename: Tzu-Chieh
authors.initials: TC
authors.lastname: Chao
authors.forename: Chuen
authors.initials: C
authors.lastname: Hsueh
authors.forename: Feng-Hsuan
authors.initials: FH
authors.lastname: Liu
authors.forename: Miaw-Jene
authors.initials: MJ
authors.lastname: Liou
authors.forename: Hsiao-Fen
authors.initials: HF
authors.lastname: Weng
mesh_terms: D000328:Adult; D002291:Carcinoma, Papillary / Q000097:blood* / Q000401:mortality / Q000601:surgery; D018265:Carcinoma, Papillary, Follicular / Q000097:blood* / Q000401:mortality / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011379:Prognosis; D015996:Survival Rate; D013954:Thyroglobulin / Q000097:blood*; D013964:Thyroid Neoplasms / Q000097:blood* / Q000401:mortality / Q000601:surgery; D013965:Thyroidectomy
chemical_list: D013954:Thyroglobulin