title: Thyroglobulin in the washout fluid of lymph-node biopsy: what is its role in the follow-up of differentiated thyroid carcinoma?
abstract: BACKGROUND
  The clinical evaluation of enlarged local lymph nodes (LNs) is difficult at the beginning and throughout the follow-up of differentiated thyroid carcinoma (DTC). Although the examination of samples collected from LNs by fine-needle aspiration biopsy cytology (FNAB-C) is extremely specific for the diagnosis of metastases, its sensitivity is low, especially in paucicellular samples.
  
  
  CONCLUSIONS
  The measurement of thyroglobulin (Tg) in the fine-needle aspiration biopsy (FNAB) washout fluid (FNAB-Tg) increases the diagnostic performance of cytology to up to 100% sensitivity and specificity. However, the application of FNAB-Tg is currently hindered by the absence of methodological standardization, a lack of definite cutoff points, and the ongoing debate regarding its accuracy in nonthyroidectomized patients, those with elevated serum Tg, and those with circulating anti-Tg antibodies.
  
  
  CONCLUSIONS
  FNAB-Tg improves the diagnostic performance of FNAB-C in LN metastases, even when the latter is unable to diagnose the metastases. For that reason, FNAB-Tg should be included in the monitoring of DTC.
authors.affiliation: 1 Department of Endocrinology & Diabetes, Federal University of Campina Grande Medical School , Campina Grande, Brazil .
authors.forename: Maria Roseneide Dos Santos
authors.initials: MR
authors.lastname: Torres
authors.forename: Sebastião Horácio
authors.initials: SH
authors.lastname: Nóbrega Neto
authors.forename: Rosalina Jenner
authors.initials: RJ
authors.lastname: Rosas
authors.forename: Aline Lemos Barros
authors.initials: AL
authors.lastname: Martins
authors.forename: André Luis Correia
authors.initials: AL
authors.lastname: Ramos
authors.forename: Thomaz Rodrigues Porto
authors.initials: TR
authors.lastname: da Cruz
mesh_terms: D001323:Autoantibodies / Q000032:analysis; D044963:Biopsy, Fine-Needle / Q000379:methods / Q000592:standards*; D002291:Carcinoma, Papillary / Q000473:pathology; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology; D009333:Neck / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D013954:Thyroglobulin / Q000097:blood* / Q000276:immunology; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D014463:Ultrasonography
chemical_list: D001323:Autoantibodies; C006606:anti-thyroglobulin; D013954:Thyroglobulin