title: Thyroid cancer risk in Belarus among children and adolescents exposed to radioiodine after the Chornobyl accident.
abstract: BACKGROUND
  Previous studies showed an increased risk of thyroid cancer among children and adolescents exposed to radioactive iodines released after the Chornobyl (Chernobyl) accident, but the effects of screening, iodine deficiency, age at exposure and other factors on the dose-response are poorly understood.
  
  
  METHODS
  We screened 11 970 individuals in Belarus aged 18 years or younger at the time of the accident who had estimated (131)I thyroid doses based on individual thyroid activity measurements and dosimetric data from questionnaires. The excess odds ratio per gray (EOR/Gy) was modelled using linear and linear-exponential functions.
  
  
  RESULTS
  For thyroid doses <5 Gy, the dose-response was linear (n=85; EOR/Gy=2.15, 95% confidence interval: 0.81-5.47), but at higher doses the excess risk fell. The EOR/Gy was significantly increased among those with prior or screening-detected diffuse goiter, and larger for men than women, and for persons exposed before age 5 than those exposed between 5 and 18 years, although not statistically significant. A somewhat higher EOR/Gy was estimated for validated pre-screening cases.
  
  
  CONCLUSIONS
  10-15 years after the Chornobyl accident, thyroid cancer risk was significantly increased among individuals exposed to fallout as children or adolescents, but the risk appeared to be lower than in other Chornobyl studies and studies of childhood external irradiation.
authors.affiliation: Department of Epidemiology and Biostatistics, University of California San Francisco, 3333 California Street, Suite 280, San Francisco, CA 94118, USA. lydia.zablotska@ucsf.edu
authors.forename: L B
authors.initials: LB
authors.lastname: Zablotska
authors.forename: E
authors.initials: E
authors.lastname: Ron
authors.forename: A V
authors.initials: AV
authors.lastname: Rozhko
authors.forename: M
authors.initials: M
authors.lastname: Hatch
authors.forename: O N
authors.initials: ON
authors.lastname: Polyanskaya
authors.forename: A V
authors.initials: AV
authors.lastname: Brenner
authors.forename: J
authors.initials: J
authors.lastname: Lubin
authors.forename: G N
authors.initials: GN
authors.lastname: Romanov
authors.forename: R J
authors.initials: RJ
authors.lastname: McConnell
authors.forename: P
authors.initials: P
authors.lastname: O'Kane
authors.forename: V V
authors.initials: VV
authors.lastname: Evseenko
authors.forename: V V
authors.initials: VV
authors.lastname: Drozdovitch
authors.forename: N
authors.initials: N
authors.lastname: Luckyanov
authors.forename: V F
authors.initials: VF
authors.lastname: Minenko
authors.forename: A
authors.initials: A
authors.lastname: Bouville
authors.forename: V B
authors.initials: VB
authors.lastname: Masyakin
mesh_terms: D000293:Adolescent; D000328:Adult; D047852:Chernobyl Nuclear Accident; D002648:Child; D015331:Cohort Studies; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007457:Iodine Radioisotopes / Q000009:adverse effects*; D008297:Male; D009381:Neoplasms, Radiation-Induced / Q000175:diagnosis*; D012307:Risk Factors; D013964:Thyroid Neoplasms / Q000209:etiology* / Q000473:pathology; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes