title: The clinical features of papillary thyroid cancer in Hashimoto's thyroiditis patients from an area with a high prevalence of Hashimoto's disease.
abstract: BACKGROUND
  The goal of this study was to identify the clinicopathological factors of co-existing papillary thyroid cancer (PTC) in patients with Hashimoto's thyroiditis (HT) and provide information to aid in the diagnosis of such patients.
  
  
  METHODS
  This study included 6109 patients treated in a university-based tertiary care cancer hospital over a 3-year period. All of the patients were categorised based on their final diagnosis. Several clinicopathological factors, such as age, gender, nodular size, invasive status, central compartment lymph node metastasis (CLNM) and serum thyroid-stimulating hormone (TSH) level, were compared between the various groups of patients.
  
  
  RESULTS
  There were 653 patients with a final diagnosis of HT. More PTC was found in those with HT (58.3%; 381 of 653) than those without HT (2416 of 5456; 44.3%; p < 0.05). The HT patients with co-occurring PTC were more likely to be younger, be female, have smaller nodules and have higher TSH levels than those without PTC. A multivariate analysis indicated that the presence of HT and higher TSH levels were risk factors for a diagnosis of PTC. In the PTC patients, the presence of HT or another benign nodule was a protective factor for CLNM, whereas no significant association was found for TSH levels.
  
  
  CONCLUSIONS
  PTC and HT have a close relationship in this region of highly prevalent HT disease. Based on the results of our study, we hypothesise that long-term HT leads to elevated serum TSH, which is the real risk factor for thyroid cancer.
authors.affiliation: Department of Head & Neck Surgery, Fudan University Cancer Hospital/Center, Department of oncology, Fudan University Shanghai Medical College, 270 Dong An Road, Shanghai 200032, PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Qing-hai
authors.initials: QH
authors.lastname: Ji
authors.forename: Yong-xue
authors.initials: YX
authors.lastname: Zhu
authors.forename: Zhuo-ying
authors.initials: ZY
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Cai-ping
authors.initials: CP
authors.lastname: Huang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shen
authors.forename: Duan-shu
authors.initials: DS
authors.lastname: Li
authors.forename: Yi
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000150:complications* / Q000453:epidemiology / Q000473:pathology*; D002291:Carcinoma, Papillary; D002648:Child; D005260:Female; D050031:Hashimoto Disease / Q000150:complications* / Q000453:epidemiology; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000150:complications* / Q000453:epidemiology / Q000473:pathology*; D013972:Thyrotropin / Q000097:blood; D055815:Young Adult
chemical_list: D013972:Thyrotropin