title: Thyroglobulin levels and thyroglobulin/thyrotropin ratio could predict the success of the ablative/therapeutic131I in the differentiated thyroid cancers.
abstract: Stimulated thyroglobulin (STg) levels in patients with differentiated thyroid carcinomas (DTCs) after total thyroidectomy (TT) and before radioactive iodine (131I) ablation/therapy (RIT) are predictive of therapeutic success but can be influenced by the thyroid-stimulating hormone (TSH) level.
  
  
  
  This study compared the reliability of the STg/TSH ratio and STg measurement in predicting the success of RIT.
  
  
  
  Sixty-three DTC patients submitted to TT were assessed retrospectively to compare the ability of STg level and the STg/TSH ratio to predict successful RIT.
  
  
  
  In this study 48 (76.2%) patients had successful RIT. The successful and unsuccessful groups received different131I doses and had different STg levels and STg/TSH ratios. The STg and STg/TSH ratio cutoff values that predicted successful RIT were 4.41 ng/mL (sensitivity of 86.7% and specificity of 77%) and 0.093 (sensitivity of 80% and specificity of 79.2%), respectively. Age, STg level, STg/TSH ratio, and131I dose were associated with successful RIT, but after multivariate analysis only STg remained associated (p < 0.05).
  
  
  
  In conclusion, our data suggest that the STg/TSH ratio and measurement of STg are equally reliable in predicting successful RIT in DTC patients.
authors.affiliation: a Internal Medicine Department , Botucatu Medical School, São Paulo State University , Unesp, Botucatu , SP , Brazil.
authors.forename: Paula Grasiele Carvalho
authors.initials: PG
authors.lastname: Trevizam
authors.affiliation: b Ophthalmology, Otorhinolaryngology and Head and Neck Surgery Department , Botucatu Medical School, São Paulo State University , Unesp, Botucatu , SP , Brazil.
authors.forename: José Vicente
authors.initials: JV
authors.lastname: Tagliarini
authors.affiliation: b Ophthalmology, Otorhinolaryngology and Head and Neck Surgery Department , Botucatu Medical School, São Paulo State University , Unesp, Botucatu , SP , Brazil.
authors.forename: Emanuel Celice
authors.initials: EC
authors.lastname: Castilho
authors.affiliation: c Pathology Department , Botucatu Medical School, São Paulo State University , Unesp, Botucatu , SP , Brazil.
authors.forename: Mariângela
authors.initials: M
authors.lastname: de Alencar Marques
authors.affiliation: d Tropical Diseases and Imaging Diagnosis Department , Botucatu Medical School, São Paulo State University , Unesp, Botucatu , SP , Brazil.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kiy
authors.affiliation: a Internal Medicine Department , Botucatu Medical School, São Paulo State University , Unesp, Botucatu , SP , Brazil.
authors.forename: Gláucia Maria Ferreira da Silva
authors.initials: GMFS
authors.lastname: Mazeto
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000097:blood* / Q000532:radiotherapy* / Q000601:surgery; D002291:Carcinoma, Papillary; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D013954:Thyroglobulin / Q000097:blood*; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000097:blood* / Q000532:radiotherapy* / Q000601:surgery; D013965:Thyroidectomy; D013972:Thyrotropin / Q000097:blood*
chemical_list: D007457:Iodine Radioisotopes; D013972:Thyrotropin; D013954:Thyroglobulin
keywords: Biological markers; prognosis; thyroglobulin; thyroid neoplasms; thyrotropin