This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hatch, M. Articles by Tronko, M. Search for Related Content PubMed PubMed Citation Articles by Hatch, M. Articles by Tronko, M. Related Collections Pediatric Endocrinology Thyroid Endocrine Oncology

A Screening Study of Thyroid Cancer and Other Thyroid Diseases among Individuals Exposed in Utero to Iodine-131 from Chernobyl Fallout

Division of Cancer Epidemiology and Genetics (M.H., A.Br., N.K., A.Bo., E.O., E.R.), National Cancer Institute, Rockville, Maryland 20852; Institute of Endocrinology and Metabolism (T.B., A.D., N.K., V.T., V.S., M.T.), 04114 Kyiv, Ukraine; Research Center for Radiation Medicine (I.L., L.K.), 04050 Kyiv, Ukraine; Urals Research Center for Radiation Medicine (E.O.), Chelyabinsk 454076, Russia; and Columbia University, College of Physicians and Surgeons (E.G., L.Z.), New York, New York 10032

Address all correspondence and requests for reprints to: Maureen Hatch, Ph.D., Head, Chernobyl Research Unit, Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 6120 Executive Boulevard, EPS 7098, Rockville, Maryland 20852. E-mail: hatchm{at}mail.nih.gov.

Background: Like stable iodine, radioiodines concentrate in the thyroid gland, increasing thyroid cancer risk in exposed children. Data on exposure to the embryonic/fetal thyroid are rare, raising questions about use of iodine 131 (I-131) in pregnant women. We present here estimated risks of thyroid disease from exposure in utero to I-131 fallout from the Chernobyl nuclear accident.

Methods: We conducted a cross-sectional thyroid screening study (palpation, ultrasound, thyroid hormones, and, if indicated, fine needle aspiration) from 2003 to 2006. Participants were 2582 mother-child pairs from Ukraine in which the mother had been pregnant at the time of the accident on April 26, 1986, or 2 months after the time during which I-131 fallout was still present (1494 from contaminated areas, 1088 in the comparison group). Individual cumulative in utero thyroid dose estimates were derived from estimated I-131 activity in the mother’s thyroid (mean 72 mGy; range 0–3230 mGy).

Results: There were seven cases of thyroid carcinoma and one case of Hurthle cell neoplasm identified as a result of the screening. Whereas the estimated excess odds ratio per gray for thyroid carcinoma was elevated (excess odds ratio per gray 11.66), it was not statistically significant (P = 0.12). No radiation risks were identified for other thyroid diseases.

Conclusion: Our results suggest that in utero exposure to radioiodines may have increased the risk of thyroid carcinoma approximately 20 yr after the Chernobyl accident, supporting a conservative approach to medical uses of I-131 during pregnancy.