Radiation Risk of Screening-Detected Diffuse Goiter in a Belarusian Cohort Exposed as Children or Adolescents to Iodine-131 after Chernobyl.

Abstract

BackgroundWe previously reported a significantly increased risk of thyroid cancer due to radioactive iodine-131 after the 1986 Chernobyl nuclear accident in a cohort of children and adolescents from Belarus. Radiation-related cancer risks were five times higher among those with diffuse goiter; however, the relationship between radiation dose and diffuse goiter is not well understood.MethodsWe used logistic regression to analyze data from 10,278 study participants [mean thyroid dose = 0.63 gray (Gy)] who were screened 10 to 15 years after exposure according to a standardized protocol, which specified thyroid size assessment by both ultrasound and palpation.ResultsDiffuse goiter was identified in 1,811 subjects and was significantly associated with 131I dose (P ConclusionsThe first systematic evaluation of radiation risks of diffuse goiter after environmental exposure found a strong, statistically significant association with thyroid dose.ImpactOur study shows that radiation exposure is associated with a significantly increased risk of developing diffuse goiter. Future epidemiologic studies of iodine-deficient irradiated populations should assess thyroid size.