Thyroid cancer after the Chernobyl nuclear accident and UNSCEAR

On the health effects of the Chernobyl nuclear power plant accident, UNSCEAR published the comprehensive evaluation for the first time in 2000, 14 years after the accident,. Here, as the reports after the Chernobyl accident, this paper picked up and examined the description of 1988, 2000, 2008, 2012, and 2017 reports. Since the Fukushima Nuclear Power Station accident, UNSCEAR's assessment of thyroid cancer after the Chernobyl accident seems to be changing. A view issued in 2016 after the first round of Fukushima Prefecture thyroid test was as follows; as for people under the age of 18 at the time of the accident, 'it is pointed out that there is a possibility of diagnosing many cancers that will not be clinically diagnosed as cancer or linked to death in the future.' Almost the same wording was seen in the UNSCEAR 2012 report. This paper also mentions occult cancer, latent cancer, and overdiagnosis. Ultrasonography has been recommended in the country's cancer screening program in South Korea and the incidence of thyroid cancer in adult females increased by 15 times in 2011 compared with in 1993, which is often mentioned as an example of overdiagnosis. In South Korea, a paper that mentioned as 'papillary thyroid micro-carcinoma is different from latent papillary thyroid carcinoma at necropsy' has been published. Before going to the reassessment of the Chernobyl accident from the experience of Fukushima accident, we should define the characteristics of 'thyroid cancer of overdiagnosis examples.' (A.O.)