Shinichi Suzuki1,2, Satoru Suzuki1,2, Toshihiko Fukushima1,2, Sanae Midorikawa1,3, Hiroki Shimura1,4, Takashi Matsuzuka5, Tetsuo Ishikawa1,6, Hideto Takahashi1, Akira Ohtsuru1,3, Akira Sakai1,7, Mitsuaki Hosoya1,8, Seiji Yasumura1,9, Kenneth E Nollet1, Tetsuya Ohira1,10, Hitoshi Ohto1, Masafumi Abe1, Kenji Kamiya1,11, Shunichi Yamashita1,12. 1. 1 Radiation Medical Science Center for the Fukushima Health Management Survey, Fukushima Medical University , Fukushima, Japan . 2. 2 Department of Thyroid and Endocrinology, Fukushima Medical University , Fukushima, Japan . 3. 3 Department of Radiation Health Management, Fukushima Medical University , Fukushima, Japan . 4. 4 Department of Laboratory Medicine, Fukushima Medical University , Fukushima, Japan . 5. 5 Department of Otolaryngology, Fukushima Medical University , Fukushima, Japan . 6. 6 Department of Radiation Physics and Chemistry, Fukushima Medical University , Fukushima, Japan . 7. 7 Department of Life Sciences, Fukushima Medical University , Fukushima, Japan . 8. 8 Department of Pediatrics, Fukushima Medical University , Fukushima, Japan . 9. 9 Department of Public Health, Fukushima Medical University , Fukushima, Japan . 10. 10 Department of Epidemiology, Fukushima Medical University , Fukushima, Japan . 11. 11 Research Institute for Radiation Biology and Medicine, Hiroshima University , Hiroshima, Japan . 12. 12 Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University , Nagasaki, Japan .
Abstract
BACKGROUND: Thyroid nodules and cancers are rare in children compared with adults. However, after the 1986 Chernobyl Nuclear Power Plant accident, a rapid increase in childhood thyroid cancer was observed. To avoid any confusion and misunderstanding of data obtained in Fukushima after the 2011 nuclear accident, baseline prevalence of thyroid nodules and cancers should be carefully assessed with standardized criteria systematically, and comprehensively applied to the population perceived to be at risk. AIMS: Under the official framework of the Fukushima Health Management Survey, the thyroids of children in Fukushima were examined using ultrasound, and the results collected in the first four years after the nuclear accident were analyzed in order to establish a baseline prevalence of childhood thyroid abnormalities, especially cancer. SUBJECTS AND METHODS: Of 367,685 people aged 18 years or younger as of April 1, 2011, who were living in Fukushima Prefecture at the time of the accident, 300,476 underwent thyroid ultrasound screening. Of those, 2108 subjects with thyroid nodules were further examined using an advanced ultrasound instrument, with standardized criteria applied to determine the need for fine-needle aspiration cytology (FNAC). FNAC results determined the need for surgery and histological confirmation of the cytological diagnosis. RESULTS: Of the 2108 rescreened subjects, 543 underwent FNAC, of whom 113 were diagnosed with malignancy or suspected malignancy. Subsequently, 99 patients underwent surgical resection, revealing 95 cases of papillary thyroid cancer, three poorly differentiated cancers, and one benign nodule. The overall prevalence of childhood thyroid cancer in Fukushima was determined to be 37.3 per 100,000 with no significant differences between evacuated and non-evacuated areas. Thyroid cancer patients had external exposure estimates of <2.2 mSv during the first four months. CONCLUSIONS: The high prevalence of childhood thyroid cancer detected in this four-year study in Fukushima can be attributed to mass screening. It clearly exceeds what is found incidentally anywhere else. Direct comparisons with any other results, even those from cancer registries, are not meaningful because of differences in methodology.
BACKGROUND: Thyroid nodules and cancers are rare in children compared with adults. However, after the 1986 Chernobyl Nuclear Power Plant accident, a rapid increase in childhood thyroid cancer was observed. To avoid any confusion and misunderstanding of data obtained in Fukushima after the 2011 nuclear accident, baseline prevalence of thyroid nodules and cancers should be carefully assessed with standardized criteria systematically, and comprehensively applied to the population perceived to be at risk. AIMS: Under the official framework of the Fukushima Health Management Survey, the thyroids of children in Fukushima were examined using ultrasound, and the results collected in the first four years after the nuclear accident were analyzed in order to establish a baseline prevalence of childhood thyroid abnormalities, especially cancer. SUBJECTS AND METHODS: Of 367,685 people aged 18 years or younger as of April 1, 2011, who were living in Fukushima Prefecture at the time of the accident, 300,476 underwent thyroid ultrasound screening. Of those, 2108 subjects with thyroid nodules were further examined using an advanced ultrasound instrument, with standardized criteria applied to determine the need for fine-needle aspiration cytology (FNAC). FNAC results determined the need for surgery and histological confirmation of the cytological diagnosis. RESULTS: Of the 2108 rescreened subjects, 543 underwent FNAC, of whom 113 were diagnosed with malignancy or suspected malignancy. Subsequently, 99 patients underwent surgical resection, revealing 95 cases of papillary thyroid cancer, three poorly differentiated cancers, and one benign nodule. The overall prevalence of childhood thyroid cancer in Fukushima was determined to be 37.3 per 100,000 with no significant differences between evacuated and non-evacuated areas. Thyroid cancerpatients had external exposure estimates of <2.2 mSv during the first four months. CONCLUSIONS: The high prevalence of childhood thyroid cancer detected in this four-year study in Fukushima can be attributed to mass screening. It clearly exceeds what is found incidentally anywhere else. Direct comparisons with any other results, even those from cancer registries, are not meaningful because of differences in methodology.
Authors: Angela M Leung; Andrew J Bauer; Salvatore Benvenga; Alina V Brenner; James V Hennessey; James R Hurley; Stacey A Milan; Arthur B Schneider; Krishnamurthi Sundaram; Daniel J Toft Journal: Thyroid Date: 2017-06-21 Impact factor: 6.568