title: Hashimoto's thyroiditis as a risk factor of papillary thyroid cancer may improve cancer prognosis.
abstract: OBJECTIVE
  Hashimoto's thyroiditis (HT) has been associated with an elevated risk of papillary thyroid cancer (PTC). To investigate the possible influence of HT on the prognosis of PTC patients, we assessed the related clinical factors linking these conditions, especially serum thyroid-stimulating hormone (TSH) concentration.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  The First Hospital of China Medical University.
  
  
  METHODS
  The demographic and histological characteristics of 2478 patients who underwent thyroidectomy at our center from 2004 to 2012 were analyzed.
  
  
  RESULTS
  Compared with patients with benign thyroid nodular disease, patients with PTC showed a significantly higher prevalence of HT (18.8% vs 7.2%, P < .001), mean TSH concentrations (2.02 ± 1.76 vs 1.46 ± 1.21 mIU/L, P < .001), and positivity rates for anti-thyroglobulin antibodies (TGAB; 40.0% vs 20.4%, P < .001) and anti-thyroid peroxidase antibodies (24.8% vs 12.5%, P < .001). These differences remained after excluding all HT patients. The TSH concentrations were significantly higher in PTC patients with HT than in those without HT (2.54 ± 2.06 vs 1.90 ± 1.66 mIU/L, P = .001). Patients with PTC and HT were younger, with a female predominance, and had smaller sized tumors with less advanced TNM stage compared with those without HT, indicating a better prognosis. Multivariate analysis showed that HT, higher TSH concentration, male sex, and TGAB positivity were independent risk factors for PTC development.
  
  
  CONCLUSIONS
  Histologically confirmed HT is associated with a significantly higher risk of PTC, due primarily to the higher serum TSH concentrations resulting from the tendency to hypothyroidism in HT. Autoimmunity is another independent risk factor for PTC but may be associated with a better prognosis.
authors.affiliation: Department of Vascular & Thyroid Surgery, The First Hospital, China Medical University, Shenyang, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Lun
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Wu
authors.forename: Qian
authors.initials: Q
authors.lastname: Xia
authors.forename: Yanshuo
authors.initials: Y
authors.lastname: Han
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Liu
authors.forename: Fengyi
authors.initials: F
authors.lastname: Wang
authors.forename: Zhiquan
authors.initials: Z
authors.lastname: Duan
authors.forename: Shijie
authors.initials: S
authors.lastname: Xin
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
mesh_terms: D001323:Autoantibodies / Q000097:blood; D015551:Autoimmunity; D002277:Carcinoma / Q000209:etiology* / Q000473:pathology; D002291:Carcinoma, Papillary / Q000209:etiology* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D050031:Hashimoto Disease / Q000150:complications*; D006801:Humans; D007037:Hypothyroidism / Q000209:etiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D009195:Peroxidase / Q000276:immunology; D011379:Prognosis; D012307:Risk Factors; D012737:Sex Factors; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000209:etiology* / Q000473:pathology; D013972:Thyrotropin / Q000097:blood*
chemical_list: D001323:Autoantibodies; C006606:anti-thyroglobulin; D013972:Thyrotropin; D009195:Peroxidase