Laboratory of Radiation Epidemiology, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea.
Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
Radiat Res. 2021 Apr 1;195(4):397-400. doi: 10.1667/RADE-20-00193.1.
In most studies on radiation workers, the incidence of thyroid cancer was determined to be higher than among the general population; this is generally assumed to be due to overdiagnosis through thyroid screening. However, there is a lack of evidence on the association between thyroid screening and increased thyroid cancer incidence in most occupational studies. In this study, we compared thyroid cancer screening rates between the general population and radiation workers with various occupations and examined the relationship between these rates and thyroid cancer incidence. We compared thyroid screening rates between radiation workers and the general population with age- and sex-standardized screening ratios (SSRs) using data from two national surveys conducted during 2015-2017 in Korea, and assessed the correlation between these ratios and age- and sex-standardized incidence ratios (SIRs) for thyroid cancer. Screening rates were higher among radiation workers than among the general population, with an overall SSR of 1.58 (95% confidence interval: 1.54-1.62). When various types of occupations were compared, those with an increased SSR also had an increased SIR. SSRs remained high even when the screening period was restricted to the year preceding the survey (the year after the establishment of guidelines for thyroid cancer screening aimed at reducing overdiagnosis). In conclusion, the increased incidence of thyroid cancer among radiation workers compared to that among the general population can be attributed mainly to increased thyroid screening rates. Additional efforts are needed to reduce unnecessary thyroid cancer screening in occupational populations, particularly in those with better access to healthcare, in terms of clinical rationale and for assessing the true increase in thyroid cancer incidence.
在大多数针对放射工作人员的研究中，甲状腺癌的发病率被确定高于普通人群；这通常被认为是由于通过甲状腺筛查过度诊断造成的。然而，在大多数职业研究中，缺乏关于甲状腺筛查与甲状腺癌发病率增加之间关联的证据。在这项研究中，我们比较了普通人群和从事各种职业的放射工作人员之间的甲状腺癌筛查率，并研究了这些比率与甲状腺癌发病率之间的关系。我们使用韩国在 2015-2017 年期间进行的两次全国性调查的数据，比较了放射工作人员和普通人群之间的甲状腺筛查率，并通过年龄和性别标准化筛查率（SSR）进行比较，还评估了这些比率与甲状腺癌的年龄和性别标准化发病率比率（SIR）之间的相关性。与普通人群相比，放射工作人员的筛查率更高，总体 SSR 为 1.58（95%置信区间：1.54-1.62）。当比较各种类型的职业时，SSR 增加的职业也具有更高的 SIR。即使将筛查期限制在调查前一年（即旨在减少过度诊断的甲状腺癌筛查指南出台后的一年），SSR 仍然很高。总之，与普通人群相比，放射工作人员中甲状腺癌发病率的增加主要归因于甲状腺筛查率的增加。需要进一步努力减少职业人群中不必要的甲状腺癌筛查，特别是在那些更容易获得医疗保健的人群中，从临床原理和评估甲状腺癌发病率真实增加的角度来看。
