Details of Fukushima Thyroid Cancer Cases Revealed at the Japan Society of Clinical Oncology Meeting

On the first day of the 52nd Annual Meeting of Japan Society of Clinical Oncology which is being held on August 28 - 30 in Yokohama City, Japan, Shinichi Suzuki, a thyroid surgeon from Fukushima Medical University in charge of the Fukushima thyroid ultrasound examination, presented some details of the surgical cases in a presentation titled "Treatment of childhood thyroid cancer in Fukushima" during the Organ Specific Symposium 03: Up-to-Date Thyroid Cancer Treatment - Thyroid Cancer in Children and Adolescents. Suzuki has consistently declined to reveal these details during sessions of the Prefectural Oversight Committee Meeting for Fukushima Health (Management) Survey as well as the Fukushima Thyroid Examination Expert Subcommittee meetings. 

From the news report, which is the only material available online containing information revealed by Suzuki, Fukushima Medical University operated on 54 of the 57 surgical cases, with 45 meeting the criteria for absolute surgical indications described at the August 24 Oversight Committee Meeting for Fukushima Health Survey, excerpted below:

(2) Regarding indications for surgery

In Japan, when thyroid cancer is suspected, absolute indications for surgery include pre-surgical tumor with a diameter equal to or greater than 10 mm, lymph node metastases, extrathyroidal extension, and distant metastases. Furthermore, tumors with a diameter of 10 mm or smaller, so-called microcarcinomas, might be followed with observation in adults. However, surgery might be indicated for microcarcinomas if they are accompanied by lymph node metastasis, distant metastasis or extrathyroidal spread, or in close proximity to the recurrent laryngeal nerve or the trachea. 


According to Suzuki, 45 cases had a tumor diameter over 10 mm or metastases to lymph nodes or other organs, with 2 having lung metastases. From the news report, it is unclear how many of the 45 had lymph node metastases. Also, the latest thyroid examination results revealed two confirmed cases of poorly differentiated cancer, and it is unclear if these two cases were the cases with lung metastases. Of the other 9 cases, 7 were in close proximity to the trachea, again meeting the surgical indications. 2 cases turned out to be precautionary surgeries based on the wishes of the patient and/or family. As about 90 % of the surgical cases had hemithyroidectomy, meaning a surgical removal of one lobe of the thyroid gland, most of the patients have some thyroid function preserved, although the risk of recurrence still exists.

In regards to the timing and place of Suzuki's report, although it would seem more appropriate for him to present the details at the Prefectural Oversight Committee Meeting for Fukushima Health Survey, the following fact must be addressed: The cases which advance beyond a certain point of the secondary examination, such as biopsy, are no longer part of the Fukushima thyroid ultrasound examination as screening but rather go under regular medical care. Therefore it appears legitimate that Suzuki presented them at an academic conference first. 

However, it's a different matter whether this was a moral act. Suzuki has been repeatedly asked by committee members and journalists to disclose more details about the surgical cases. There have been many speculations about whether there have been overdiagnosis and overtreatment, creating a lot of arguments and confusion. Suzuki maintained Fukushima Medical University was following the diagnostic criteria, yet he would not reveal details. He said at one of the committee meetings that Fukushima Medical University would be fulfilling its social responsibility towards Fukushima residents by submitting academic papers to inform the world of what is happening. Although the Fukushima Health Survey is intended to watch over the health of residents and stand by them, many Fukushima residents distrust Fukushima Medical University enough to refuse participation. Fukushima Medical University's social responsibility should be, first and foremost, to maintain an honest and transparent relationship with residents. In that sense, Suzuki has effectively failed them.

By the way, those over age 18 no longer qualify for free medical care for Fukushima children. As 57 of the 104 confirmed or suspected of cancer were over age 18, more than half of them are facing a financial burden (Japan's National Health Insurance requires 30% copay) in addition to a physical and psychological burden of having cancer, as the treatments and follow-ups are conducted as part of regular medical care.

Incidentally, President of the 52nd Annual Meeting of Japan Society of Clinical Oncology, Seiichi Takenoshita, is Professor and Chairman of the Department of Organ Regulatory Surgery, Fukushima Medical University. In other words, he is Suzuki's boss.

Suzuki is scheduled to speak again during the August 30 Fukushima Session called “Message from Fukushima,” featuring Shunichi Yamashita as a keynote speaker. Yamashita will speak on "Scope for the future of Fukushima; resilience creation after the nuclear accident." Suzuki's presentation is called "Radiation exposure and thyroid ultrasound examination from the data of the Fukushima Health Management Survey."


Below is a complete translation of the Nikkei article, originally by Kyodo, posted online at 10:05 pm on August 28, 2014.

Children with Thyroid Cancer “Unlikely To Be the Effect of the Nuclear Accident,” Fukushima Examination Reported at an Academic Meeting

On August 28th, Professor Shinichi Suzuki from Fukushima Medical University reported details about surgical cases of children who were diagnosed to have strong suspicion of cancer at the Japan Society of Clinical Oncology meeting held in Yokohama City. These children were diagnosed during the thyroid examination conducted by Fukushima Prefecture because of the Tokyo Electric Fukushima Daiichi nuclear power plant accident. 

After presenting his viewpoint that cancer cases were unlikely to be the effect of the nuclear accident, Suzuki referred to some opinions about possibilities of overdiagnoses and unnecessary surgeries. He emphasized that “treatment was based on the [diagnostic] criteria.” 

Fukushima Prefecture’s thyroid examination targets approximately 370,000 residents who were younger than 18 at the time of the disaster/accident. So far 57 children have been confirmed to have cancer, and 46 are “suspected of cancer.” Comparing to the 1986 Chernobyl nuclear power plant accident which saw a skyrocketed increase in pediatric thyroid cancer, Suzuki stated, “[Fukushima is] different from Chernobyl in terms of symptoms and age distribution.”

Regarding the 54 cases, out of 57 cancer cases, operated on at Fukushima Medical University, 45 cases, or a little over 80%, exhibited tumor diameter over 10 mm or metastases to lymph nodes or other organs, meeting the diagnostic criteria for surgery. Two cases had lung metastases.

Remaining 9 cases had tumor diameter equal to or less than 10 mm and had no metastases, but in 7 of them, “Surgery was appropriate as the tumor was in close contact with the trachea.” Close observation and follow-up was deemed appropriate for [the remaining] 2 cases, but they were operated on based on the wishes of the patients and/or their families.

About 90% of the 54 cases operated on had hemithyroidectomy (removal of one lobe of the thyroid gland).

Regarding the thyroid cancer in Fukushima, some experts raised a question, “Did all of the cases operated on actually need surgery?” and some have requested disclosure of the patient data. (Kyodo)

First Round of Fukushima Thyroid Examination Complete: Provisional Results Show 57 Confirmed and 46 Suspected Cases of Thyroid Cancer, A Total of 103 Cases.

Sixteenth Prefectural Oversight Committee for Fukushima Health Survey convened on August 24, 2014, releasing the latest results of the thyroid examination, consisting of the near-complete results of the preliminary examination over the last three years, intended to obtain a baseline, as well as the partial results from the regular examination, which will keep track of any changes.

Official English translation of the results are available here.

The initial round of thyroid examination, the preliminary examination, finished as of March 31, 2014. Although not all the examinations have been completed, the provisional results, as of June 30, 2014, were released.The second round of thyroid examination, the regular examination, testing everyone again beginning with areas exposed to higher radiation doses, has already begun.

A summary of the results of the preliminary examination is provided below:

Total number of children examined as of June 30, 2014: 296,026

Total number of children whose initial examination results are confirmed: 295,689
     Assessment A1  152,389 (51.5%) (no nodules or cysts found)
     Assessment A2  141,063 (47.7%) (nodules 5.0 mm or smaller or cysts 20.0 mm or smaller)
     Assessment B     2,236 (0.8%) (nodules 5.1 mm or larger or cysts 20.1 mm or larger)
     Assessment C         1 (0.0%) (requiring immediate secondary examination)

Translation of some tables from the results of thyroid preliminary examination:

Page 3

Initial examination progress status

Number and proportion of nodules and cysts

Secondary examination includes more detailed thyroid ultrasound, blood and urine tests, and fine-needle aspiration biopsy if warranted.
      2,237 are eligible for secondary examination
      1,951 have actually undergone secondary examination
      1,848 finished the secondary examination

Page 4

Secondary examination progress status

Pages 5-6
2  Summary of fine-needle aspiration biopsy results
(1) Results of biopsy (as of June 30, 2014)

(2) Regarding indications for surgery

In Japan, when thyroid cancer is suspected, absolute indications for surgery include pre-surgical tumor with a diameter equal to or greater than 10 mm, lymph node metastases, extrathyroidal extension, and distant metastases. Furthermore, tumors with a diameter of 10 mm or smaller, so-called microcarcinomas, might be followed with observation in adults. However, surgery might be indicated for microcarcinomas if they are accompanied by lymph node metastasis, distant metastasis or extrathyroidal spread, or in close proximity to the recurrent laryngeal nerve or the trachea. 

In our thyroid examination, participants who are found to be in the B or C assessment category during the primary examination go onto the secondary examination. Biopsy is recommended based on the findings of the repeat ultrasound examination. If the biopsy shows confirmed or suspected malignancy, they will be treated according to the above indication criteria, with adequate informed consent. 

In addition, treatment guideline mentioned above has been discussed at the Diagnostic Criteria Assessment Subcommittee of the Thyroid Examination Expert Committee, consisting of specialists from related specialty societies.

Thyroid Ultrasound Diagnostic Guidebook 2010 (Edited by Japan Association of Endocrine Surgeons and Japan Society of Thyroid Surgery)
Thyroid Ultrasound Diagnostic Guidebook, revised, 2nd edition (Edited by The Japan Association of Breast and Thyroid Sonology and Thyroid Terminology and Diagnostic Criteria Committee)
Thyroid Nodule Treatment Clinical Guidelines 2013 (Edited by Japan Thyroid Association)


Commentary by the writer/translator: 

In summary, there were 14 more cancer cases, 4 boys and 10 girls, confirmed since the last report on May 19, 2014. All 14 cases came from the FY2013 targeted municipalities, where the secondary examination is still ongoing. 

The total number of cases confirmed or suspected of cancer is 104. Of these, 59 had surgeries as of June 30, 2014 and 1 turned out to be a benign nodule, 55 were confirmed to be papillary thyroid cancer, and 2 were confirmed as poorly differentiated thyroid cancer. Additionally, 46 were "suspected" of having thyroid cancer. (The total number of cases confirmed or suspected of cancer is often reported as 103 in news reports, excluding the case confirmed to be benign). 

In the Asahi Shimbun article, released in the morning of August 24, 2014 and contained apparently leaked information, Fukushima Medical University was quoted as saying it was unlikely that these cancer cases were related to radiation exposure.

Although the data is incomplete as the results from the Aizu area, part of the FY2013 municipalities, are not all available, a table was provided for regional comparison.

Page 10
Table 9: Proportions of subjects in B&C assessment categories as well as confirmed/suspected of malignancy (provisional)

Note 10: Excluding duplicate data and unconfirmed results
Note 11: The number of participants whose fine-needle aspiration biopsy results, done before June 30, are confirmed.  
Note 12: Excluding one case that was suspected of malignancy but turned out to be benign after surgery
Note 13: Tamura City, Minamisoma City, Date City, Kawamata Town, Hirono Town, Naraha Town, Tomioka Town, Kawauchi Village, Okuma Town, Futaba Town, Namie Town, Katsurao Village and Iitate Village
Note 14: Fukushima City, Koriyama city, Shirakawa City, Sukagawa City, Nihonmatsu City, Motomiya City, Koori Town, Kunimi Town, Otamamura Village, Kagamiishi Town, Tenei Village, Nishigou Village, Izumizaki Village, Nakajima Village, Yabuki Town, Tanagura Town, Yamatsuri Town, Hanawa Town, Samegawa Village, Ishikawa Town, Tamakawa Village, Hirata Village, Asakawa Town, Furudono Town, Miharu Town, and Ono Town
Note 15: Iwaki City, Soma City, Shinchi Town
Note 16: Aizuwakamatsu City, Kitakata City, Shimogo Town, Hinoemata Village, Tadami Town, Minamiaizu Town, Kitashiobara Village, Nishiaizu Town, Bandai Town, Inawashiro Town, Aizubange Town, Yugawa Village, Yanaizu Town, Mishima Town, Showa Village, and Aizumisato Town

〈Results and Discussion of regional comparison〉

 A regional analysis was conducted of 295,689 participants who underwent the primary examination, excluding those who were confirmed to be duplicate entries and those whose results have not been finalized.

The result of the analysis revealed the rate of assessment categories B & C tended to increase in the order of “13 municipalities including the evacuation zone,” “Nakadori,” “Hamadori.” and Aizu Region.

On the other hand, the rate of of those “confirmed or suspected of malignancy” was almost the same in “13 municipalities including the evacuation zone,” “Nakadori,” and “Hamadori,” and slightly lower in “Aizu region.” This could be due to the fact that Aizu region has a lower proportion of secondary examination participants who actually completed it.

(End of page 10)


Commentary by the writer/translator: 

As a reference to grasp the geographical relationship of these regions, the map below, excerpted from the August 25, 2014 Fukushima Minyu article, color-codes the above comparison regions.
          Red: 13 municipalities including the evacuation zone
          Blue: Nakadori
          Yellow: Hamadori
          Green: Aizu region


However, this particular grouping of municipalities to form comparison regions is drawing some criticisms as it may not be a good reflection of how the radioactive plume spread. For instance, Hamadori as defined here, which is not exactly the same as the conventional Hamadori, clumps Iwaki City where the highly radioactive plume hit, together with two municipalities up north on the Fukushima-Miyagi border, which did not receive as much plume. Also, a municipality might not be uniformly contaminated depending on its topography.


As for the partial results of the regular examination (the second round of examination), 28,575 have gone through the primary examination from the 2014 targeted municipalities, out of 213,223 eligible, and results have been determined for 6,458 of them. There were 46 in the B assessment category, but it was unclear if all of these individuals were also in the B category in the preliminary examination, or if any of these cases are newly diagnosed.

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.


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?


Fukushima Thyroid Examination February 2020: 186 Surgically Confirmed as Thyroid Cancer Among 237 Cytology Suspected Cases

Highlights   The third round: 1 case newly diagnosed as suspicious or malignant, and 5 new cases surgically confirmed.  The fourth ...