title: Longitudinal study on the correlations of thyroid antibody and thyroid hormone levels after radiotherapy in patients with nasopharyngeal carcinoma with radiation-induced hypothyroidism.
abstract: BACKGROUND
  The purpose of this study was to evaluate the correlations of thyroid antibody and thyroid hormone in postradiotherapy (post-RT) patients with nasopharyngeal carcinoma (NPC).
  
  
  METHODS
  Serum thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), thyroperoxidase antibody (anti-TPO), and thyroglobulin antibody (anti-TG) levels of 55 patients with NPC were taken before RT and at 3, 6, 12, and 18 months after RT. Patients with hypothyroidism at 18 months after RT and those with normal thyroid function were categorized into the hypo and normal groups, respectively. The thyroid antibody levels were compared between the 2 groups, and the correlations of thyroid antibody and thyroid hormone were evaluated for the hypo group.
  
  
  RESULTS
  The anti-TPO and anti-TG of the hypo group were higher than the normal group. In the hypo group, there was a positive correlation (r = 0.51) between TSH and anti-TG and a negative correlation between fT4 and anti-TPO (r = -0.55).
  
  
  CONCLUSIONS
  There were correlations of the thyroid antibody and thyroid hormone levels in patients with radiation-induced hypothyroidism.
authors.affiliation: Cancer Hospital, Shantou University Medical College, Shantou, Guangdong, China.
authors.forename: Zhixiong
authors.initials: Z
authors.lastname: Lin
authors.forename: Linxing
authors.initials: L
authors.lastname: Chen
authors.forename: Yusen
authors.initials: Y
authors.lastname: Fang
authors.forename: Aiqun
authors.initials: A
authors.lastname: Cai
authors.forename: Tuodan
authors.initials: T
authors.lastname: Zhang
authors.forename: Vincent W C
authors.initials: VW
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002277:Carcinoma; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000175:diagnosis* / Q000209:etiology*; D007155:Immunologic Factors / Q000097:blood; D007453:Iodide Peroxidase / Q000097:blood; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy; D011237:Predictive Value of Tests; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects*; D012680:Sensitivity and Specificity; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D007155:Immunologic Factors; C006606:anti-thyroglobulin; D014284:Triiodothyronine; D013972:Thyrotropin; D007453:Iodide Peroxidase; D013974:Thyroxine
keywords: nasopharyngeal carcinoma; postradiotherapy; radiation-induced hypothyroidism; thyroid antibodies; thyroid hormones