title: National incidence and prevalence of TSH-secreting pituitary adenomas in Sweden.
abstract: BACKGROUND
  TSH-secreting pituitary adenomas (TSHomas) are rare. Epidemiological data are scant and there are no reports on national incidence.
  
  
  OBJECTIVE
  The objective of the study was to estimate the national Swedish incidence and prevalence of TSHomas.
  
  
  METHODS
  This was an observational study.
  
  
  METHODS
  The study was conducted at tertiary referral centers.
  
  
  METHODS
  The Swedish Pituitary Registry and World Health Organization International Statistical Classification of Diseases and Related Health Problems coding at all university hospitals were used to identify patients diagnosed with TSHomas 1990-2010. The identified patients' medical records were studied until the latest follow-up [median 5.0 years (range < 1-20 years)].
  
  
  METHODS
  Incidence, prevalence, demographics, tumor characteristics, treatment outcome, and thyroid hormone level at diagnosis were measured.
  
  
  RESULTS
  The age-standardized national incidence of 28 TSHoma patients was 0.15 per 1 million inhabitants per year, with an increasing incidence over time (0.05 per 1 million per year in 1990-1994 to 0.26 per 1 million per year in 2005-2009). The national prevalence in 2010 was 2.8 per 1 million inhabitants, in which 0.85 per 1 million had active disease. Most patients (n = 22) underwent pituitary surgery, 5 had radiotherapy, and 6 had somatostatin analogues. Eighteen patients were considered cured at the latest follow-up; 25% remained uncontrolled. Subjects treated for putative primary hyperthyroidism prior to diagnosis had TSH levels more than double those with intact thyroid at diagnosis (P = .013). The median time to diagnosis was longer for women than men (4 vs < 1 year, P = .026). More women than men were treated surgically (94.1% vs 54.5%, P = .022).
  
  
  CONCLUSIONS
  This is the first estimate of a national incidence of TSHoma. Additional epidemiological studies are needed to compare these results with other geographical areas. This study suggests an increased incidence of TSHomas, in agreement with reports on other pituitary adenomas.
authors.affiliation: Sahlgrenska Academy, University of Gothenburg, SE-405 30 Göteborg, Sweden.
authors.forename: Lisa
authors.initials: L
authors.lastname: Ónnestam
authors.forename: Katarina
authors.initials: K
authors.lastname: Berinder
authors.forename: Pia
authors.initials: P
authors.lastname: Burman
authors.forename: Per
authors.initials: P
authors.lastname: Dahlqvist
authors.forename: Britt Edén
authors.initials: BE
authors.lastname: Engström
authors.forename: Jeanette
authors.initials: J
authors.lastname: Wahlberg
authors.forename: Helena Filipsson
authors.initials: HF
authors.lastname: Nyström
mesh_terms: D000236:Adenoma / Q000453:epidemiology* / Q000378:metabolism / Q000628:therapy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000453:epidemiology* / Q000378:metabolism / Q000628:therapy; D015995:Prevalence; D012042:Registries; D013548:Sweden / Q000453:epidemiology; D013963:Thyroid Hormones / Q000627:therapeutic use; D013972:Thyrotropin / Q000378:metabolism*; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013963:Thyroid Hormones; D013972:Thyrotropin