The 3rd International Symposium on the Fukushima Health Management Survey
This symposium was held on Feb 13-14, 2021, in Fukushima City, Japan, and the chief members of the Fukushima Health Management Survey and related Japanese academic societies participated as speakers.＜movie＞
Prof. Kenji Kamiya (Fukushima Medical University) introduced the present status of the thyroid examination in which the effects of radiation exposure are not detected. He emphasized that it is too early to draw conclusions, and the thyroid examination should be continued without prejudice.
Prof. Tomotaka Sobue (Osaka University) introduced the concept of overdiagnosis and stated that overdiagnosis is hard to understand even for experts, and special ingenuity is required to disseminate knowledge.
Prof. Gerry Thomas (Imperial College London), who was involved in preparing the recommendations for thyroid examination monitoring after the nuclear accident as a member of IARC, introduced the proposal of IARC on her slide as follows (movie 08:05:50).
Recommendation 1
If the thyroid exposure dose is below 100-500 mSv after the nuclear accident, do not perform thyroid screening in the population.
Recommendation 2
A long-term thyroid monitoring program should be considered for individuals at higher risk after the nuclear accident.
After the lecture, she said that she recognizes that the thyroid examination performed in Fukushima is monitoring, rather than screening as defined by IARC (movie 08:07:00).
Prof. Hiroki Shimura (Fukushima Medical University) made a presentation on the current status of thyroid examination. He explained that having thyroid ultrasonography allows for early detection of thyroid cancer, which benefits patients by reducing the recurrent rate (movie 05:53:00). He also explained that the thyroid examination performed in Fukushima is not screening but monitoring by the definition of IARC, and IARC recommends carrying out monitoring according to the actual situations in the affected area(movie 05:50:40).
The core members of JCJTC found some misleading information in this symposium.
1. What Prof. Thomas presented were not IARC recommendations. The original recommendations are as follows:
Recommendation 1
The Expert Group recommends against population thyroid screening after a nuclear accident.Recommendation 2
The Expert Group recommends that consideration be given to offering a long-term thyroid monitoring program for higher-risk individuals(those exposed in utero or during childhood or adolescence with a thyroid dose of 100–500 mGy or more) after a nuclear accident.2. What is now undergoing in Fukushima is screening but not monitoring. All children are undergoing in-school examination by ultrasonography, and they are not given a chance to select the way of their follow-up or talk to a doctor.
3.There is no evidence to prove early detection of thyroid cancer by ultrasonography can reduce the recurrent rate.