title: Is there an association between thyroid function abnormalities and breast cancer?
abstract: OBJECTIVE
  The aim of this study was to evaluate the association between thyroid function abnormalities and breast cancer and, in particular, the prognostic markers of breast cancer..
  
  
  METHODS
  Baseline levels of thyrotropin, free triiodothyronine, free thyroxine and thyroid autoantibodies were measured in 97 women with primary breast cancer, 27 women with benign breast disease, and 4 women with atypical ductal hyperplasia. Their baseline levels were compared with those in 48 healthy women with a normal mammography in the last 2 years.
  
  
  RESULTS
  There were no significant associations between history of thyroid disease and breast cancer (p = 0.33). The mean baseline levels of triiodothyronine and thyrotropin did not differ significantly between the compared groups. The mean baseline levels of free thyroxine were found to be significantly higher in the breast cancer group, even after adjusting for thyroid replacement therapy. The presence of thyroid antibodies did not differ significantly between the compared groups. In a subgroup analysis, breast cancer cases with thyroid disease and particularly hypothyroidism had a significantly lower incidence of lymph node metastases compared with breast cancer cases without thyroid disease.
  
  
  CONCLUSIONS
  Our data confirmed the proliferative effect of thyroid hormones on breast cells, which had previously been shown in vitro. Additionally, thyroid disease and particularly hypothyroid function appeared to be associated with a lower incidence of lymph node metastases. Further studies to determine the prognostic role of thyroid hormones in breast cancer are warranted.
authors.affiliation: Department of Internal Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Greece.
authors.forename: Anna
authors.initials: A
authors.lastname: Angelousi
authors.affiliation: Department of Internal Medicine, Medical School, National and Kapodistrian University of Athens, Greece.
authors.forename: Evanthia
authors.initials: E
authors.lastname: Diamanti-Kandarakis
authors.affiliation: Department of Endocrinology and Diabetes, Alexandra Hospital, Athens, Greece.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Zapanti
authors.affiliation: Department of Pathology, Medical School, Laiko Hospital, National and Kapodistrian University of Athens, Greece.
authors.forename: Afroditi
authors.initials: A
authors.lastname: Nonni
authors.affiliation: National School of Public health, National and Kapodistrian University of Athens, Greece.
authors.forename: Eftuxios
authors.initials: E
authors.lastname: Ktenas
authors.affiliation: Endocrinology laboratory of Evgenidion hospital, Athens, Greece.
authors.forename: Aimilia
authors.initials: A
authors.lastname: Mantzou
authors.affiliation: Department of Propaedeutic Surgery, Laiko General Hospital, University of Athens Medical School, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Kontzoglou
authors.affiliation: Department of Propaedeutic Surgery, Laiko General Hospital, University of Athens Medical School, Greece.
authors.forename: Grigorios
authors.initials: G
authors.lastname: Kouraklis
mesh_terms: D001323:Autoantibodies / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011379:Prognosis; D013961:Thyroid Gland / Q000098:blood supply / Q000503:physiopathology*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine