title: Development, characterization and clinical validation of new sensitive immunofluorometric assay for the measurement of serum thyroglobulin.
abstract: OBJECTIVE
  In the last decade, data published stressed the role of highly-sensitive thyroglobulin (Tg) assays in the follow-up of differentiated thyroid carcinoma (DTC) patients. The present study describes a new, highly-sensitive Tg assay, compares it with an available commercial assay, and validates it in the follow-up of DTC patients.
  
  
  METHODS
  The immunofluorometric high-sensitivity Tg assay is based on monoclonal and polyclonal antibodies produced at our laboratories. It was validated in 100 samples of 87 patients with DTC submitted to total thyroidectomy, 87% of whom also received radioiodine. For correlation, all samples were also tested using a commercial Tg assay (Beckman Access) with functional sensitivity (FS) of 0.1 ng/mL.
  
  
  RESULTS
  The new method showed FS of 0.3 ng/mL. The correlation between the two methods was good (r = 0.74; p < 0.0001). The diagnostic sensitivity was 88.9%, and it was increased to 100% when combined with neck US.
  
  
  CONCLUSIONS
  This new, high-sensitivity Tg assay presented a good correlation with Beckman Access assay and with the clinical outcome of the patients. The continuous availability of a validated assay is an additional advantage for long term follow-up of DTC patients.
authors: Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors: Cláudia C D
authors: CC
authors: Nakabashi
authors: Rosa Paula M
authors: RP
authors: Biscolla
authors: Teresa S
authors: TS
authors: Kasamatsu
authors: Teresinha T
authors: TT
authors: Tachibana
authors: Rafaela N
authors: RN
authors: Barcelos
authors: Eduardo Z
authors: EZ
authors: Malouf
authors: Danielle M
authors: DM
authors: Andreoni
authors: Rui M B
authors: RM
authors: Maciel
authors: José Gilberto H
authors: JG
authors: Vieira
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D005260:Female; D015200:Fluoroimmunoassay / Q000379:methods / Q000592:standards*; D006801:Humans; D008297:Male; D051379:Mice; D008875:Middle Aged; D011817:Rabbits; D012680:Sensitivity and Specificity; D013954:Thyroglobulin / Q000097:blood*; D013964:Thyroid Neoplasms / Q000175:diagnosis; D055815:Young Adult
chemical_list: D000911:Antibodies, Monoclonal; D013954:Thyroglobulin