title: Stimulated thyroglobulin at recombinant human TSH-aided ablation predicts disease-free status one year later.
abstract: BACKGROUND
  Thyroglobulin (Tg) levels measured at the time of remnant ablation after thyroid hormone withdrawal (THW) were shown to have prognostic value in predicting disease-free status.
  
  
  OBJECTIVE
  Our objectives were to determine whether stimulated Tg levels, measured at the time of remnant ablation performed under recombinant human TSH (rhTSH) stimulation, has value in predicting absence of detectable disease 1 year after radioiodine therapy and to compare the results obtained with this approach with a cohort of patients submitted to ablation after THW.
  
  
  METHODS
  This was a prospective observational study.
  
  
  METHODS
  The study included 293 consecutive patients treated for a differentiated thyroid carcinoma with no initial evidence of distant metastasis. All patients were submitted to a total or near-total thyroidectomy, followed by ablation either under rhTSH (n = 151) or endogenous TSH stimulation (n = 142). Patients with positive Tg antibodies were excluded.
  
  
  METHODS
  The predictive value of Tg at ablation was assessed by receiver operating characteristic curve analysis.
  
  
  RESULTS
  In the rhTSH group, 96 patients (73.3%) were considered disease-free at 1 year. Stimulated Tg at ablation after rhTSH was found to be an independent prognostic indicator of disease persistence 12 months later. The highest-accuracy cutoff value for absence of detectable disease was defined as 7.2 ng/mL, with a negative predictive value of 90%. In the THW group, Tg at ablation also proved to have independent predictive value. Using the same threshold (7.2 ng/mL), the negative predictive value of Tg was 95% in the THW group.
  
  
  CONCLUSIONS
  When rhTSH was used, stimulated Tg at ablation had independent predictive value for disease-free status 1 year later. A low stimulated Tg at rhTSH-aided ablation may be considered a favorable prognosis factor.
authors.affiliation: University Hospital of Coimbra, Department of Endocrinology, Diabetes and Metabolism, Praceta Mota Pinto, 3000-075 Coimbra, Portugal. jmiguelmelo@live.com.pt.
authors.forename: Miguel
authors.initials: M
authors.lastname: Melo
authors.forename: Gracinda
authors.initials: G
authors.lastname: Costa
authors.forename: Cristina
authors.initials: C
authors.lastname: Ribeiro
authors.forename: Francisco
authors.initials: F
authors.lastname: Carrilho
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Martins
authors.forename: Adriana Gaspar
authors.initials: AG
authors.lastname: da Rocha
authors.forename: Manuel
authors.initials: M
authors.lastname: Sobrinho-Simões
authors.forename: Manuela
authors.initials: M
authors.lastname: Carvalheiro
authors.forename: Paula
authors.initials: P
authors.lastname: Soares
mesh_terms: D000328:Adult; D002454:Cell Differentiation; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013954:Thyroglobulin / Q000097:blood*; D013964:Thyroid Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000601:surgery*; D013965:Thyroidectomy; D057073:Thyrotropin Alfa / Q000008:administration & dosage
chemical_list: D057073:Thyrotropin Alfa; D013954:Thyroglobulin