A Surprising Disclosure During the Ninth Session of the Ministry of the Environment Expert Meeting

A Surprising Disclosure During the Ninth Session of the Ministry of the Environment Expert Meeting


Shigenobu Nagataki appeared to be low-keyed during the ninth session of the Expert Meeting Regarding the Status of Health Management of Residents Following the Tokyo Electric Fukushima Daiichi Nuclear Power Plant Accident held on August 5th, 2014. Perhaps he was still reeling from the aftermath of the last sessioni ii, held on July 16th, when he was bombarded with five outspoken expert witnesses.

During the ninth session, Nagataki's demeanor was hesitant yet assertive, trying to build a consensus as a chairman. At one point he reiterated the purpose of the Expert Meeting as the place for experts to seriously consider what is really the best way to manage the health of those who were affected by the disaster, as if he were trying to remind himself. He also made a few statements suggestive of imposing a burden of responsibility on each committee member.

However, it almost seemed as if he were beginning to alienate some of the committee members due to the unreasonable way he was carrying out the proceedings. He seemed in a hurry to wrap up the dose assessment portion of the discussion, but some of the committee members expressed objections to the dose assessment summaryiii, prepared by the MOE to be included in the interim report, citing too many uncertainties regarding the dose assessment itself to draw a hasty conclusion. This was the summary which Nagataki was working hard to have endorsed by the committee. In particular, Toshimitsu Honma from Japan Atomic Energy Agency (JAEA) pointed out the prepared summary could be misleading, since it included two contradictory statements which could not coexist scientifically: One statement was that it was unlikely that residents were exposed to doses over 100 mSv, while the other was that the possibility of someone receiving over 100 mSv exposure dose could not be ruled out.

In short, the table seemed to be turned: Nagataki no longer appeared to be in control.

Another committee member, Hiromi Ishikawa from Japan Medical Association, suggested that the committee move onto discussions on health survey and medical measures, as he has been told there would only be two more session scheduled. Honma added on, stating that the completion of dose assessment and risk assessment isn’t necessarily required for the discussion on health survey. The Ministry of the Environment (MOE) official quickly declared that they weren’t limited to just two more sessions. It appeared that the entire atmosphere of the Expert Meeting shifted to allow for more time for future discussion.

Meanwhile, the citizens’ group from the Kanto area, comprising of concerned parents from Ibaraki Prefecture, western Chiba Prefecture and eastern Saitama Prefecture where hot spots can be found, submitted to the MOE Vice-Minister Tomoko Ukishima a formal request to remove Nagataki as a chairman. In addition, a few members of the audience, under the strict prohibition from vocalizing any opposition, silently held up signs stating, “We don’t need a skewed chairman” and “Do you have any conscience?” (Incidentally, these actions possibly led to even more strict and tightened guidelinesiv for the audience for the next session on August 27, 2014, absolutely prohibiting any sort of display of opinions, verbal or written, and requiring the audience candidate to agree to such a condition when they enter their names into a lottery selecting the actual audience.

Also during the ninth session, there was an unexpected disclosure of crucial information from one of the two expert witnesses, Akira Miyauchi, a thyroid, breast, and endocrine surgeon from Kuma Hospital, a hospital in Kobe, Hyogo Prefecture, which specializes in thyroid illnesses. First, as an expert witness, he gave an overview of thyroid microcarcinomav. He emphasized that the data was from adults and therefore it might not be extrapolated to children, and that there was very little data available for pediatric microcarcinoma of thyroid gland, in general as well as at Kuma Hospital.

When Nagataki askedvi if an early detection of small thyroid cancer would mean hemithyroidectomy, where only a half of the thyroid gland is removed, preserving some thyroid function and eliminating the need for administration of thyroid hormone, Miyauchi stated,”Papillary thyroid cancers tend to occur in multiples. Therefore, even though the thyroid cancer might be discovered when small, it might still be necessary to conduct a total thyroidectomy [meaning the removal of the entire thyroid gland]. Removing smaller (3 to 9 mm) cancers would significantly increase the number of total thyroidectomies performed. To be honest with you, even though the complication rate might be low, an increased number of total thyroidectomies would inevitably lead to some cases of permanent hypoparathyroidism. Therefore, I don’t think it is a good idea to operate on every case. “

Fukushima Medical University Vice President Masafumi Abe chimed in to defend the validity of thyroid cancer cases which have been operated on so far. “Fukushima Medical University has been conducting thyroid ultrasound examination, and so far there are a total of 90 confirmed or suspected malignant cases. Of these, 51 had surgeries and 50 were confirmed to be cancer, including microcarcinoma smaller than 10 mm. Our facility is only operating on cases which are deemed high risk.”

Miyauchi followed, “To supplement what was just stated, I am also a member of the Diagnostic Criteria Inquiry Subcommittee of the Thyroid Examination Expert Committee. The day before yesterday I attended the subcommittee meeting where the information about the surgical cases at Fukushima Medical University was presented. According to the presentation, at least over 70% of the cases had conditions which would be ordinarily considered appropriate for surgery, based on our current standard of care, such as the tumor size over 1 cm, the presence of lymph node metastases, or some aggressive cases with distant metastases. Regarding the remaining 30%, Dr. Suzuki explained that those cases were operated on as they were what we consider high risk, such as being near the recurrent laryngeal nerve or contacting the trachea.”

This statement by Miyauchi immediately caught everyone's attention, especially in the social stream timeline for the Ustream channel for OurPlanet-TVvii, where the Internet audience was writing in comments while watching the Expert Meeting in real time. Details regarding the Diagnostic Criteria Inquiry Subcommittee, established on September 18, 2011, have been sketchy. Its existence was mentioned during the fourth session of the Prefectural Oversight Committee Meetings for Fukushima Health Management Surveyviii. It was established to bring consistency to examinations on evacuees residing outside Fukushima Prefecture, and composed of thyroid specialists, endocrine and thyroid surgeons, pediatric endocrinologists, and ultrasound specialists. What is known up to this point was that the subcommittee consisted of the following seven organizations:

  • Japan Thyroid Associationix
  • Japan Association of Endocrine Surgeonsx 
  • Japan Society of Thyroid Surgeryxi 
  • The Japan Society of Ultrasonics in Medicinexii 
  • The Japan Society of Sonographers xiii 
  • The Japanese Society for Pediatric Endocrinologyxiv
  • The Japan Association of Breast and Thyroid Sonologyxv

However, no record could be found, at least on the Internet, regarding the proceedings of the “Diagnostic Criteria Inquiry Subcommittee.” A freelance journalist, Ryuichi Kino, tweeted that the document obtained through information disclosure was heavily redacted, with the names of the subcommittee members blacked out.

Miyauchi’s self-admittance that he was a subcommittee member, therefore, was a pleasant surprise. He was disclosing information that was not readily provided by Shinichi Suzuki, a thyroid surgeon at FMU in charge of the thyroid examination, at the third session of the Thyroid Examination Assessment Subcommittee, held on June 10, 2014, when Kenji Shibuya, an epidemiologist and a public health specialist from the University of Tokyo, raised a possibility of over-diagnosis and over-treatmentxvi. At the time, all Suzuki would admit, defending the decision to operate, was that some cases had lymph node metastases or hoarseness [which indicates the involvement of the recurrent laryngeal nerve]. Suzuki would not give the percentage of the cases which actually had lymph node metastases or hoarseness. He even said he wasn’t the one who decided not to reveal the information.

Miyauchi’s revelation essentially validated the surgeries performed at FMU so far, dispelling the criticism that the screening was harmful and not really warranted.

Then, quite curiously, Nagataki started off the question and answer session by presenting a hypothetical situation to Miyauchi, saying, “For instance, if we conduct a screening, some cancers would always be discovered. If we continue on with the screening and remove all the cancers we find even though some may not have risks [of becoming aggressive] because there is a sense of security in simply removing anything that might remotely be dangerous, ultimately one in ten or one in one hundred children in Fukushima might end up getting their thyroid glands removed. Some might say that would be acceptable as long as it brought a sense of security. What do you think about such an idea?”

Miyauchi quickly said, as if reprimanding Nagataki, “I think the numbers you just gave are rather extreme.”

Then Miyauchi continued, “As I mentioned earlier, I am a member of the Diagnostic Criteria Inquiry Subcommittee of the Fukushima Thyroid Examination Expert Committee, so I am quite familiar with why the thyroid screening is being conducted in Fukushima Prefecture. As we know that pediatric thyroid cancer notably increased after the Chernobyl accident, and most members of the general public are aware of it and worried whether thyroid cancers would also increase in Fukushima. Given such a concern, for one thing, a scientific assessment had to be carried out to see if there would actually be an increase. The other thing is to monitor the health of the residents. I understand both of these issues are rather difficult issues. Based on these conditions, as mentioned earlier, what should be done is to do everything according to certain criteria; to conduct an examination according to a certain criterion, to read the ultrasound image according to a certain criterion, to decide whether or not to conduct fine needle aspiration biopsy according to a certain criterion, and so on. This is what is happening in Fukushima Prefecture. For instance, our hospital has examined Fukushima residents who moved to the Kansai area, at the request of FMU. The ultrasound examination data is not assessed by us. Instead, it is sent to FMU to be read according to a certain criterion. If the fine needle aspiration biopsy is needed, we will conduct the biopsy based on instructions from FMU and send the specimen to FMU. So my understanding is that they are making an effort to maintain a certain standard in every way possible.”

Mass screening is almost always accompanied by a possibility of over-diagnosis and over-treatment. In case of thyroid cancer, surgery is not risk-free. In the previous sessions of the MOE Expert Meeting, pros and cons of cancer screenings were discussed, especially in relation to adult cancer screenings, given the fact the residents had concerns regarding their health after having been exposed to the radioactive releases from FDNPP. Gen Suzuki suggested the exposure dose was too low to warrant the screening. The consensus of the seventh session of the MOE Expert Meeting, citing the low exposure doses, appeared to be on the passive side in regards to offering health checkups, including cancer screenings, to the Fukushima residents outside of the evacuation zone as well as the residents of neighboring prefectures.

There even appeared to be movements, both by a certain group of citizens and citizen scientists on Twitter and by some experts, like the University of Tokyo researchers, to do away with the thyroid ultrasound examination of those who were 18 or younger at the time of the accident, claiming over-diagnosis and over-treatment.

However, the biggest issue was that Fukushima Medical University lacked transparency to disclose information necessary for the outside experts to properly evaluate the situation.

Miyauchi’s statement at least validates the way Fukushima Medical University is handling surgical cases. However, his statement also raises a concern that there are so many thyroid cancers which are considered high risk. After all, Shunichi Yamashita and Shinichi Suzuki kept saying that these cancers were considered latent cancers which would not be discoverable until much later in life. The reality is that these are clinically obvious cancers, and the question would be why there are so many such cases. The government and Fukushima Medical University have maintained that the thyroid abnormality rates, such as nodules, cysts, and even cancer, do not differ between Fukushima Prefecture and the rest of the nation (citing the MOE study in Yamanashi, Aomori and Nagano Prefecturesxvii), in an attempt to dispel any relationship between the thyroid abnormalities and radiation exposure.

On August 24, 2014, the sixteenth session of the Assessment Committee for the Fukushima Prefecture Health Survey is to be held. It is expected that the full report of the first round (FY2011-2013) of the thyroid ultrasound examination will be released, along with some of the result from the second round which has already begun.

We must keep close tabs on how the number of thyroid cancer cases might change from the first to the second round. If it's truly a screening effect, the second round should not yield as many thyroid cancers. Meanwhile, FMU needs to be more transparent, sharing some crucial information with the medical and scientific communities, of course, with a full consideration to preserve patient confidentiality. Suzuki mentioned that FMU was accumulating all sorts of data from the thyroid examination, including the radiation exposure data, so that studies could be published. He said that was the way FMU was trying to fulfill its social responsibility. However, their social responsibility really should rest on the residents first, not so much the publication of scientific paper.


References

Questioning the Very Status of the Ministry of the Environment Expert Meeting Regarding the Status of Disaster Victims' Health Management



Questioning the Very Status of the Ministry of the Environment
Expert Meeting Regarding
the Status of Disaster Victims' Health Management

It might have been a slip of a tongue, but Chairman Shigenobu Nagataki, an emeritus professor at Nagasaki University, a former chairman of Radiation Effects Research Foundation, and a mentor to infamous Shunichi Yamashita, appeared to be speaking earnestly when he said, "Committee members, please do not hesitate to ask questions. Given what was just stated, it will be disastrous for this committee to have to conclude that there is an actual increase in thyroid cancer [due to the Fukushima accident]." Toshihide Tsuda, a physician and an epidemiologist at Okayama University, has just emphatically stated that in certain Fukushima municipalities there was a clear evidence of a thyroid cancer epidemic in those who were 18 or younger at the time of the March 2011 accident. Calling this an “outbreak, occurring only 3.1 to 3.2 years after the accident,” Tsuda stressed that in the near future, thyroid cancer would begin to appear in those with relatively longer latency periods, which means a quick action is needed to secure adequate medical resources in order to be able to provide diagnosis and treatment in a timely manner.

This conversation happened during the eighth session of the Expert Meeting Regarding the Status of Health Management of Residents Following the Tokyo Electric Fukushima Daiichi Nuclear Power Plan Accident, held by the Ministry of the Environment on July 16, 2014. The Expert Meeting was originally established in order to discuss the health care and radiation exposure aspects of the Children and Disaster Victims Support Act, which was approved by the Diet in June 2012.

As a background, Fukushima Prefecture is already conducing health management survey for the residents utilizing a fund established by the national government. However, the national government is in need of discussing the current status of health management and its challenges in Fukushima Prefecture as well as the surrounding prefectures from a medical viewpoint. In addition, the Children and Disaster Victims Support Act requires the national government to take any necessary measures regarding surveys on radiation health effects. Based on these needs, the Expert Meeting was established within the Ministry of the Environment to discuss, from an expert perspective, the status of measures for grasping and assessing exposure doses, health management, and medical care.

Fundamentals of the Children and Disaster Victims Support Act are summarized as follows:

  • providing accurate information;
  • supporting the choice of residing, moving and returning based on the intention of disaster victims;
  • making efforts for prompt alleviation of health concerns from radiation exposure;
  • giving due consideration so that disaster victims do not face unwarranted discrimination;
  • giving special consideration for children (including fetuses) and pregnant women;
  • and continuing a long-term and reliable support for radiation effects as long as needed.

Issues discussed at the MOE Expert Meeting were in particular related to the Article 13 of the Children and Disaster Victims Support Act, in regards to the study on health effects of radiation exposure and the provision of medical care. The Article 13 reads as follows:

  1. In order to clarify the situation of radiation exposure caused by the Tokyo Electric nuclear accident, the national government shall take measures such as estimating radiation exposure doses and assessing exposure doses using tests effective for dose assessment, and any other necessary measures.
  2. The national government shall take necessary measures in regards to implementing regular medical checkups for the disaster victims and conducting other surveys of health effects from radiation exposure due to the Tokyo Electric nuclear accident. In this case, necessary measures should be taken so that those who have resided in areas with radiation levels measured above a certain threshold as children (including those who were in utero when their mothers resided in such areas), or those in equivalent circumstances, shall have lifelong medical checkups.
  3. In relation to the medical expenses to be borne by children or pregnant women who are disaster victims (excluding medical care relating to injuries or illnesses not caused by radiation exposure due to the Tokyo Electric nuclear accident), the national government shall take necessary measures to reduce the financial burden or any other measures relating to the provision of medical care to the disaster victims.

A point of contention at the MOE Expert Meeting, headed by Nagataki, has been the dose assessment, especially the direct measurements of thyroid glands of 1,080 children (age 0 to 15), conducted in late March 2011. Nagataki seemed determined to utilize the direct measurement data, which concluded that nobody exceeded 50 mSv, despite critical issues such as a small sample size and high background radiation levels. He has been trying to build an “expert consensus” regarding the validity of the direct measurement data. However, guest presentations by experts at the Expert Meeting have revealed that the contamination level of clothing, not the background air dose rate, was used as the background radiation level, which was subtracted from the actual count to obtain the exposure dose. This could have potentially resulted in underestimation.

In addition, Nagataki emphasized how the high kombu (a type of seaweed with especially high iodine content) consumption rate amongst the Japanese offered protective effects against radioactive iodine, given the fact the majority of children never received stable iodine tablets for thyroid blocking before exposure to the radioactive plume. However, the actual consumption amount of kombu in last 40 years has gone down, for reasons such as the introduction of western food in the 1970s. According to Nagataki's presentation at the 2007 American Thyroid Association meeting, the average dietary iodine intake from seaweeds was 1.2 mg/day in Japan1. However, kombu consumption appears to be decreasing each year, especially in younger families with children which consumed one-third of average amount of seaweed consumption, due to decreased consumption of traditional foods. Children's dietary intake from seaweeds might be a quarter to one-third of Nagataki's outdated claim.

As each session of the Expert Meeting progressed, Nagataki worked towards building a consensus to “scientifically” validate the 1,080 screening data for dose assessment and thus the basis for estimating health risks, despite its shortcomings. The exposure dose estimate from the 1,080 screening data, well below 100 mSv, which is widely regarded by regulators and radiation protection specialists as the level cancers might increase, would allow the government to claim that health risks is too low to necessitate expansion of medical checkups to wider areas and age groups. At the seventh session held on June 25, 2014, Nagataki pointed out2 that “Times are different between now and when the Children and Disaster Victims Support Act was approved. We now have more dose assessment data which allow us to talk about the health risks scientifically. This is a huge difference,” when Hiromi Ishikawa, the executive director of Japan Medical Association, pressed for consideration of introduction of medical checkups in hotspots outside Fukushima Prefecture, such as Matsudo and Kamagaya in Chiba Prefecture, based on the principle of the Children and Disaster Victims Support Act.

As a matter of fact, in his attempt to build an expert consensus, Nagataki appeared not to take into consideration opinions of outside experts if they differed from his. Even more, he appeared to be trying to disregard the very mission of the Expert Meeting: discussing radiation health effects and health management on the basis of the Children and Disaster Victims Support Act.

This became the most apparent at the July 16th session, as depicted in the July 22 Tokyo Shimbun article, translated into English here.

Tsuda, one of the five expert witnesses invited, claims that the current “outbreak” of thyroid cancers in Fukushima children cannot be explained by the “screening effect,” when the data is analyzed and compared with the national cancer statistics as well as within Fukushima Prefecture against municipalities with the lowest exposure dose.


Table 1 Comparison of thyroid cancer detection probabilities within Fukushima Prefecture
(Prevalence Odds Ratio determined against Aizu and Soma areas as the control).



Critical of the commonly accepted notion that health effects do not occur below 100 mSv, Tsuda presented numerous published studies that proved otherwise. In fact, he by far exceeded 10 minutes allotted for each of the five expert witnesses that day, and Nagataki had to nudge him to wrap up more than twice. Tsuda defiantly replied, “This Expert Meeting has not brought up these studies [as it should have], so I must do it [for you],” and went on until he was done.

Tsuda explained that in outbreak epidemiology, which was developed as an investigative tool in studying disease outbreaks where the cause isn't always apparent, the effect (disease) is what is studied and dealt with. He called the Expert Meeting's fixation on dose assessment “backwards” and “a mere laboratory method.” Tsuda said to Nagataki, “We must remember that this is an issue of humans.”

Tsuda also said that the Expert Meeting should consider the fact that all age groups including pregnant women were still being exposed to radiation in Fukushima Prefecture. This drew an applause from the audience of general public, which made Nagataki displeased. He said, “Um, this applause...haven't the audience been asked not to applause ahead of time?” This statement also appeared to startle Nagataki and other members, such as Otsura Niwa, a retired Kyoto University Professor who holds a position of Special Professor at Fukushima Medical University. Both Nagataki and Niwa, in disbelief, had to confirm with Tsuda what he meant. Tsuda said, “We are all being exposed to radiation in Japan, except the air dose rate is higher in Fukushima.”

During the debate following the presentations by the witnesses, there were some questions regarding Tsuda's presentation as described in this post. Tsuda insisted that the World Health Organization (WHO) report clearly stated thyroid cancer, leukemia, breast cancer and other solid cancers would increase. In response, Niwa talked3 about the dilemma he faced as a member of the WHO Health Risk Assessment Expert Group, which compiled Health risk assessment from the nuclear accident after the 2011 Great East Japan earthquake and tsunami, based on a preliminary dose estimation4 in February 2013.

Niwa felt that doses were overestimated due to various issues with assumptions utilized in dose estimation. He repeatedly asked the Expert Group to employ more realistic methods to estimate doses, but the Expert Group chose to stick to higher estimate doses, taking a conservative and cautious approach based on a radiation protection concept. Niwa says he disagreed with the Expert Group's decision and argued that the conservative approach certainly would be reasonable and indeed very important in a prospective estimation, but that it would not be appropriate to retrospectively estimate unnecessarily high doses in those who were already exposed. Niwa disclosed during the discussion that he suggested reducing the estimated doses by one-tenth, but that the Expert Group never incorporated his suggestion. (After the meeting was over, Tsuda and Niwa carried out further, informal discussion on whether the thyroid cancer cases in Fukushima were due to the screening effect or not. Tsuda asked Niwa if he has ever read a single published study regarding a screening effect. Niwa replied, “No, not myself.” Tsuda, speaking with a freelance journalist, Oshidori Mako, expressed his disappointment and frustration with the Expert Meeting, as the so-called experts were not even familiar with studies published on health effects of radiation below 100 mSv. Tsuda felt that it was impossible to carry out sufficient arguments as the grasp of the basic knowledge differed so much).

During the concluding statement, Nagataki acknowledged that the consensus of the Expert Meeting to accept United Nations Scientific Committee on the Effects of Atomic Radiation's (UNSCEAR's) approach to assessing health risks, based on dose estimation, appeared to differ vastly from the opinions of the witnesses. He stated that the Expert Meeting was taking a serious care to consider [the well-being of] the disaster victims and earnestly discussing the best way to carry out health management for them. This statement contradicts the statement he made at the June 25 session, dismissing the Children and Disaster Victims Support Act. Most of all, if the Expert Meeting were seriously considerate of the disaster victims whose true exposure doses are unknowable, due to the lack of sufficient early exposure data, why would it be disastrous for this Expert Meeting to have a conclusion that cases of thyroid cancers might be increasing? The Expert Meeting would be truly serving the disaster victims if it fully embraces its mission to expertly discuss radiation health effects and health management, adhering to the principles of the Article 13 of the Children and Disaster Victim Support Act, from the viewpoint of precautionary principle, rather than having prejudged conclusions.

Other important issues to be raised about this Expert Meeting have to do with the potential conflict of interest. For instance, Niwa, also a member of International Committee on Radiation Protection (ICRP) , is known to have received financial support from the Federation of Electric Power Companies of Japan for his travel expenses to the ICRP meetings5. Although the WHO Expert Group cleared his conflict of interests in this matter, citing his expertise in molecular biology and radiation biology, he certainly appears to have a conflict of interest for the MOE Expert Meeting.

Niwa is not the only one with the potential conflict of interest. Chairman Nagataki is currently a chairman of the board of Radiation Effects Foundation6, which arranged financial assistance from the Federation of Electric Power Companies of Japan to Niwa. Some of the members, Nobuhiko Ban and Toshimitsu Honma, were involved with the making of UNSCEAR Fukushima report. Yasuhito Sasaki is a former committee chairmann of UNSCEAR.

With the deviation from its original mission and the apparently predetermined conclusion to underestimate health risks, along with the potential conflicts of interest in multiple members, is it not time to question the very status of the Expert Meeting Regarding the Status of Health Management of Residents Following the Tokyo Electric Fukushima Daiichi Nuclear Power Plant Accident?


References:

The Ministry of the Environment Expert Meeting: Witnesses Propose “A Drastic Overhaul of Medical Checkups and Dose Assessment”

(This is a translation of an article on the website of OurPlanet-TV, a Japanese independent media, which summarized the eighth session of the Ministry of the Environment Expert Meeting Regarding the Status of Health Management of Residents Following the Tokyo Electric Fukushima Daiichi Nuclear Power Plan Accident which was held on July 16, 2014. Tokyo Shimbun article regarding the same session is translated here).
*****

The Ministry of the Environment Expert Meeting: Witnesses Propose "A Drastic Overhaul of Medical Checkups and Dose Assessment

Fukushima Thyroid Examination Fact Sheet: May/June 2014

Below is a synopsis of the thyroid ultrasound examination, being conducted in Fukushima Prefecture since October 2011. The synopsis is intended to organize and clarify available information regarding thyroid cancer cases discovered in Fukushima residents, who were ages 18 or younger at the time of the March 2011 Fukushima nuclear accident. It also includes some information gathered from various committee meetings, conducted and streamed live online only in Japanese. 



Fukushima Thyroid Examination Fact Sheet: May/June 2014

In October 2011, seven months after the Fukushima Dai-ichi nuclear power plant meltdowns and explosions, Fukushima Prefecture began thyroid ultrasound examination, as part of Fukushima Health Management Survey1 (now called Fukushima Health Survey), in over 360,000 children. These children were younger than 18 at the time of the accident, and most of them did not receive adequate protection of stable iodine tablets for prevention of thyroid cancer. This was intended to be the baseline examination to assess the current condition of their thyroid glands. The thyroid gland is known to be affected, especially in children, by radioactive iodine 131 emitted from a nuclear accident.

The plan was to conduct the preliminary (first-round) thyroid ultrasound examination in all 360,000 plus children, beginning with municipalities with the highest radiation exposure doses. With Fukushima Medical University (FMU) being the sole conductor of the examination initially, as commissioned by Fukushima Prefecture, the first round of the examination was completed in late March 2014, at the end of Fiscal Year 2013. Cumulative results have been released every 2 to 4 months2, as the examination progressed on each year's cohort.

The final results of the first round of thyroid ultrasound examination from October 2011 to March 2014 are not yet known as of May 2014, since the secondary examination has not been completed. However, the results tallied up to March 31, 2014 were released on May 19, 2014, at the 15th Prefectural Oversight Committee Meeting for Fukushima Health Survey3.

Thyroid ultrasound examinations conducted on 295,511 Fukushima children (final results known for 287,056 children as of February 21, 2014) since October 2011, revealed that 136,804 children (47.7%) had an "A2" assessment, with either cysts 20.0 mm or smaller or nodules 5.0 mm or smaller. In addition, 2,069 children (0.7%) had a B assessment, indicating cysts 20.1 mm or larger or nodules 5.1 mm or larger, qualifying them for secondary examinations, including a more detailed ultrasound examination, blood and urine tests checking for thyroid function and iodine excretion, and fine-needle aspiration biopsy if necessary. Of these 2,069 children, 1,754 actually received the secondary examination.

So far, there are 49 papillary thyroid cancer cases, which were the most common form of thyroid cancer found in children after the 1986 Chernobyl accident, and 39 have suspect biopsies, meaning they need surgery to obtain a section of thyroid gland for tissue biopsy. Another cancer case is suspected to be of the poorly-differentiated subtype, with the final tissue diagnosis pending. The total number of confirmed thyroid cancer cases is 50, and the total number of confirmed and suspected cancer cases is 90 (this number is sometimes reported as 89, excluding one case that was confirmed to be benign). 32 were male and 58 were female, with an average age of 14.7 ± 2.7 (age range 6-18) at the time of the accident. The tumor size ranged from 5.1 mm to 40.5 mm. The youngest was a girl who was 6 at the time of the accident.

The incidence, or more accurately, prevalence, is thus 30.1 per 100,000 overall or 16.6 per 100,000 for confirmed cases so far. Although it is not possible at this time to determine if these cancers are radiation-induced or not, drawing on Japanese cancer incidence statistics, 3 or fewer cases of thyroid cancer would be expected in this population per year. (In 2010, normal incidence of thyroid cancer in Japan was 0.1 in 100,000 below age 15 and 1.1 in 100,000 in age 15-194,5). According to the National Cancer Institute, pediatric thyroid cancer incidence in the US, is 0.2 in 100,000 below age 15 and 1.76 per 100,000 in age 15-19 (12.2 in 100,000 in adults6).

So far, the official consensus of the Ministry of the Environment (MOE) of the Japanese government, FMU, and the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR) appears to be that the finding constitutes a “screening effect,” which means thyroid cancer is being discovered as all children in Fukushima Prefecture are screened7,8. MOE also conducted a study in distant prefectures, supposedly unaffected by radiation exposure, but the study population is not age- and sex-matched to the Fukushima cohort and the two datasets cannot be directly compared9.

It should be noted that about 20% of the 368,651 Fukushima children never underwent the first round of thyroid ultrasound examination for various reasons. In addition, about 15% of the 2,070 children are yet to undergo the required secondary examination, and 10% of the 1,754 who underwent the secondary examination are still awaiting their results.

In the full-scale examination beginning April 2014, those born between April 2, 2011 and April 1, 2012 will be included, some of who were exposed in utero, making the total to be examined 385,000 in a two-year period. Fukushima Prefecture is now offering more facilities to conduct the examination in Fukushima. Agreements have been signed with various medical facilities nationwide to conduct the thyroid examination, so that 17,634 children residing outside Fukushima Prefecture can have an easier access.


Additional information:

Shunichi Yamashita, in charge of the Fukushima Health Survey until March 2013, initially claimed any thyroid cancer discovered during the screening would be latent cancers which would not have been discovered until much later if the screening hadn't been conducted.

At the June 2013 meeting of the Thyroid Examination Assessment Subcommittee, Shinichi Suzuki, an FMU professor currently directing the thyroid examination, admitted that some of the 50 cancer cases had lymph node metastasis or symptoms such as hoarseness which validated thyroidectomy. Suzuki had also maintained these cancers represented latent cancers.

This revelation came when Suzuki was grilled about the possibility of overdiagnosis and overtreatment by one of the subcommittee members, Kenji Shibuya10, a public health specialist at the University of Tokyo Graduate School of Medicine. Shibuya co-authored an article raising the issue of thyroid cancer overdiagnosis and overtreatment, published in Lancet11 in May 2014.

Although Suzuki mentioned the existence of conditions which would justify surgery, he would not release any detailed data such as the actual number of such cases. However, his admittance of lymph node metastasis in some of the cases seems to contradict the initial claim that these cancers were latent cancers which would never have been found.

This is a controversial topic, and we are awaiting a release of some of the data by FMU. By the way, although no longer attending the Prefectural Oversight Committee Meeting for Fukushima Health Survey, Shunichi Yamashita remains as the senior director of thyroid ultrasound examination12.

5 Matsuda A, Matsuda T, Shibata A, Katanoda K, Sobue T, Nishimoto H and The Japan Cancer Surveillance Research Group. Cancer Incidence and Incidence Rates in Japan in 2008: A Study of 25 Population-based Cancer Registries for the Monitoring of Cancer Incidence in Japan (MCIJ) Project. Japanese Journal of Clinical Oncology, 44(4): 388-396, 2013

The July 22 Tokyo Shimbun article, "Running Backwards on Health Support After the Nuclear Accident: Ministry of Environment Expert Meeting"

On July 22, 2014, Tokyo Shimbun published an article titled, "Running Backwards on Health Support After the Nuclear Accident: Ministry of Environment Expert Meeting." The entire article is only available in the paper edition as in the image below, but it has been written out in this blog post.



Below is the complete English translation of this article.


Running Backwards on Health Support After the Nuclear Accident: Ministry of Environment Expert Meeting

The Ministry of the Environment (MOE) Expert Meeting Discussing Health Support After the Fukushima Nuclear Accident is taking an unthinkable twist. At the July 16th meeting, an outside researcher asked for the expansion of health checkups, but the committee chair looked the other way, stating “I don’t want to discuss the issue.” The expansion of health checkup is part of the Act Concerning Support for Children and Disaster Victims, but the committee chair himself voiced an opinion, “We now have different circumstances from when the Act was first approved.” There is no way disaster victims can accept such attitudes. (by T. Sakakibara)

◆ Hesitant on the Expansion of Health Checkups

“Radioactive materials [being disseminated due to the Fukushima nuclear accident] are not thought to remain within borders of Fukushima Prefecture. We need to urgently figure out if there are any cases in non-Fukushima residents. We should not be fixated only on dose assessments.”

It was the Ministry of the Environment Expert Meeting held on July 16th. An invited guest speaker Toshihide Tsuda, an epidemiologist and an Okayama University professor, challenged the current state of the meeting spending time on discussing what the exposure dose was for residents within and out of Fukushima Prefecture.

However, Shigenobu Nagataki, the committee chair and a former chairman of Radiation Effects Research Foundation, pushed aside what Professor Tsuda pointed out, stating, “You are extremely unique.”

Fukushima Prefecture began the Prefectural Resident Health Survey immediately after the accident, including thyroid examination for those who were under age 18 at the time of the accident. However, the central government currently pays for health examination only for Fukushima residents. Therefore, the Expert Meeting is presently discussing whether other areas might need health checkups.

Chairman Nagataki has set a policy to: 1) Assess the exposure dose for residents within and out of Fukushima Prefecture; 2) Analyze health effects based on the dose; and 3) Consider which health support might be necessary. At the last meeting (the seventh session) on June 26th, the rough outline of dose assessment was finally put together.

The outline, based on the dose estimates by an Independent Administrative Institution, National Institute of Radiological Sciences, as well as the behavior questionnaire of residents by Fukushima Prefecture, stated that the internal exposure dose from radioactive iodine that can cause thyroid cancer was “mostly under 50 mSv.” In regards to the external exposure dose, it noted that “The survey finding, ’99.8% was under 5 mSv in Fukushima Prefecture,’ could be reasonably applied to see the overall tendency.”

However, there are large uncertainties in this assessment result.

Only about 1,000 had direct measurements of exposure from radioactive iodine taken, which is 0.3% of residents eligible for thyroid examination by Fukushima Prefecture. Radioactive iodine has a short half-life of 8 days and cannot be measured now. Behavior questionnaires for external dose assessment had a low response rate of only 25.9%.

During the meeting, Professor Tsuda claimed, “When considering a causal relationship between an illness and a cause, data for the cause often tends to be scant. It is a principle of international epidemiological analysis to see it from the side of the illness. Considering the cause first is merely a laboratory method.”

In addition, he continued, “Fixating on dose assessments will delay countermeasures, worsening the damage.” He emphasized that health checkups should be immediately carried out within and out of Fukushima Prefecture, in order to identify cases of thyroid cancer and other illnesses and to analyze whether the number of cases increased after the accident or whether there are regional differences.

Despite inviting Professor Tsuda to the meeting, Chairman Nagataki practically ignored his opinion.

To this response [by Nagataki calling him unique], Professor Tsuda retorted, “My opinions are based on a textbook published by Oxford University Press. Chairman, you are the one that is unique.” However, Chairman Nagataki unilaterally cut off the conversation, stating, “I have no intention of arguing with you. We are going to carry on discussion based on exposure dose.”

◆ Not Meeting the Expectations by Residents

Passive assessments of radiation health effects by the Japanese government predate this meeting.

The Cabinet Office expert meeting, “Working Group (WG) on Risk Management of Low-dose Radiation Exposure,” put together a report in December 2011, concluding, “…increased risk of cancer from low-dose radiation exposures at 100 mSv or less is so small as to be concealed by carcinogenic effects from other factors, making verification of any clear cancer risk from radiation exceedingly challenging.” 

The Cabinet Office WG was also headed by Nagataki. It also included other members of the MOE expert meeting, such as Ostura Niwa, a special professor at Fukushima Medical University, and Keigo Endo, president of Kyoto College of Medical Science.

The expert meeting, at this point of time, is leaning in the direction of “Radiation health effects cannot be proven,” and “As the effects cannot be proven, even health checkups within Fukushima Prefecture are unnecessary,” since the exposure dose within and out of Fukushima Prefecture is expected to be significantly lower than 100 mSv.

In fact, the expert meeting already has some opinions hesitant on expanding health checkups.

The Act Concerning Support for Children and Disaster Victims [English translation here], approved in June 2012, asks for expansion of health checkups as well as reduction of medical expenses, but Chairman Nagataki cast doubt on the need for it at the seventh session, stating “Circumstances are quite different now compared to the time when the act was approved,” and, “As the dose assessment has progressed, we can now make scientific statements in regards to the risk.”

Likewise, during the same session, a member of the expert meeting and a professor at Osaka University, Tomotaka Sobue, explained disadvantages of health checkups using the term, “overdiagnosis.”

This means that since a slow-growing cancer, such as thyroid cancer, has a possibility of never becoming symptomatic in lifetime and causing damages to the body, discovery of cancer during health checkups could cause excessive anxiety and a psychological and physical burden due to surgery.

Another member and the clinic director at International University of Health and Welfare, Gen Suzuki, claimed “An adequate debate needs to be carried out as to whether the best answer is to conduct health checkups as a response to anxiety by residents regarding their health.”

However, requests for expansion of health checkups are swelling from the side of the parties involved, the residents.

On July 13th, there was an event in Metropolitan Tokyo for mothers from within and out of Fukushima Prefecture to talk about life after the nuclear accident.

One of the participants, Kaoru Inagaki (age 42), a member of citizen’s group, Kanto Children Health Survey Support Fund, which conducts thyroid examination in four prefectures including Tochigi, Ibaraki, Chiba and Saitama, said, “When we announce openings for the examination, they are immediately taken up.”

Another participant, Kumi Kanome (age 46), a mother who evacuated with a second-grade daughter to Kanagawa Prefecture from Otama Village, Fukushima Prefecture, appealed, “The nuclear accident increased our worries about children’s illnesses. It is natural for us to want to have them checked out. Regardless of whether living in or outside Fukushima Prefecture, any mother would feel that way.”

Emiko Ito (age 51), director of the event organizer, non-profit organization “National Parents Network to Protect Children from Radiation,” said, “The expert meeting is ignoring the Act Concerning Support for Children and Disaster Victims. That won’t be conducive to resolving residents’ anxiety. It only leads to mistrust.”

Some of the members of the expert meeting have different views. One of them, Hiromi Ishikawa, Executive Director of Japan Medical Association, criticizes, “The present expert meeting does not reflect opinions of the residents. I don’t know why anybody would just one-sidedly tell worried people, ‘It’s okay.’”

From a stand point of “nobody knows the effect of low-dose radiation exposure,” he says, “We need to quickly consider whether there are any illnesses due to radiation and how to deal with them if there are any. Worries can be only resolved when we are prepared that way.”

“Advantages and disadvantages of health checkups are not something that can be uniformly decided by those who are called experts. We need to establish the system for health checkups and let the residents, who are the parties involved, decide.”

Memo from the editing desk:
Mr. Nagataki is running the expert meeting. This fact alone makes it clear how the government has summed up the Fukushima nuclear accident. The predecessor of Radiation Effects Research Foundation was the United States Atomic Bomb Casualty Commission (ABCC), which “investigated the effects of atomic bombs without treatment.” A network originating there was involved in developing the “Myth of Infallible Safety.” Now they are working hard to spread the “Myth of Reassurance.”

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