Fukushima Thyroid Examination June 2017: 190 Thyroid Cancer Suspected/Confirmed (6 Additional Cases)


  • The third round sees its first 4 cases of suspected/confirmed thyroid cancer: Overall, 6 suspected/confirmed cases were newly diagnosed by cytology since the last report.
  • Seven additional surgeries since the last report: the number of surgically confirmed cancer cases =152 (101 in the first round, 49 in the second round, and 2 in the third round)
  • Total number of suspected/confirmed thyroid cancer = 190 (excluding a single case of benign tumor; 116 in the first round, 71 in the second round, and 4 in the third round)
  • The second round screening data is still not final (confirmatory examination still ongoing).
  • OUT: a third-party expert committee. IN: a United Nations expert group.
On June 5, 2017, the 27th Oversight Committee for Fukushima Health Management Survey was held in conjunction with the 7th Thyroid Examination Assessment Subcommittee in Fukushima City, Fukushima Prefecture. Among other information, the Oversight Committee released the latest results (as of March 31, 2017) of the second and third rounds of the Thyroid Ultrasound Examination (TUE). Also released was an updated version of the first round results. Official English translation of the results are posted here. The narrative below includes other information covered during the committee meeting and the subsequent press conference.

This Oversight Committee meeting was unprecedentedly held in conjunction with the Thyroid Examination Assessment Subcommittee. Two meetings were merged in the usual two-and-a-half-hour allotted for the Oversight Committee meeting alone. Some members overlap between the two meetings, and it was difficult to discern which position they were speaking from. Although the reconvening of the Thyroid Examination Assessment Subcommittee was promised—for the purpose of analyzing the second round results—at the last Oversight Committee meeting, the joint session format was not anticipated. It certainly didn't seem very productive. Nevertheless, the authorities seemed not too concerned, perhaps because the joint session format simply may have been a way for the committee/subcommittee members to wrap up the current term ending on July 9, 2017.

As of March 31, 2017, 2 more cases of suspected thyroid cancer have been diagnosed from the second round. The third round now have 4 cases of suspected thyroid cancer, making a grand total of 190 (191 including the single case of post-surgically confirmed benign nodule) for the first, second and third round screening results combined. The number of surgically confirmed cancer cases, excluding the aforementioned case of benign nodule, increased by 7 (101 from the first round, 49 from the second round, and 2 from the third round), and the remaining 38 (14 from the first round, 22 from the second round, and 2 from the third round) continue to be under the observational follow-up. 

The second round screening (the first Full-Scale screening) was originally scheduled to be conducted from April 2014 through March 2016, and the primary examination (with the participation rate of 71.0% and the progress rate of 100.0%), is essentially complete. But the confirmatory examination (with the participation rate of 82.3% and the progress rate of 95.4%) is still ongoing. 

The third round screening (the second Full-Scale Screening) began on May 1, 2016 and is scheduled to run through March 2018—the end of Fiscal Year 2017. As of March 31, 2017, 120,596 out of the survey population of 336,616 residents have participated in the ongoing primary examination at the participation rate of 35.8%. The confirmatory examination began on October 1, 2016 with the participation rate of 48.0% and the progress rate of 67.8% so far. 

Full-Scale Screening (second and third rounds)
To be conducted every 2 years until age 20 and every 5 years after age 20, the Full-Scale screening began with the second round screening (the first Full-Scale Screening) in April 2014, including those who were born in the first year after the accident. There are 381,256 eligible individuals born between April 2, 1992 and April 1, 2012. As of March 31, 2017, 270,511 have actually participated in the primary examination. 

The participation rate went up by 0.1% to 71.0%, but it is lower than 81.7% from the first round screening. Results of the primary examination have been finalized in 270,511 participants, and 2,226 (no increase since the last Oversight Committee meeting) turned out to require the confirmatory examination. 

The confirmatory examination is still ongoing for the second round. Of 2,226 requiring the confirmatory examination, 1,832 have participated at the participation rate of 82.3% (increased from the previous 79.5% but still lower than 92.9% from the first round screening). So far 1,748 have received final results including 200 that underwent fine needle aspiration cytology (FNAC) which revealed 71 cases suspicious for cancer, of which 2 cases were newly diagnosed. 

Confirmation of thyroid cancer requires pathological examination of the resected thyroid tissue obtained during surgery. There has been 5 additional surgical cases since the last reporting. As of March 31, 2019, 49 underwent surgery and 48 were confirmed to have papillary thyroid cancer. One remaining case was confirmed to have "other thyroid cancer" according to the classification in the seventh revision of Japan's unique thyroid cancer diagnostic guidelines. A specific diagnosis was not revealed, but it has been reported as a differentiated thyroid cancer that is not known to be related to radiation exposure and it is allegedly neither poorly differentiated thyroid cancer nor medullary cancer. 

The third round screening or the second Full-Scale Screening has covered 120,596 or 35.8% of the survey population of 336,616. The primary examination results have been finalized in 105,966 or 87.9% of the participants, revealing 691 to require the confirmatory examination. Results of the confirmatory examination have been finalized in 225 of 332 (67.8%) that have been examined. FNAC was conducted in 11 individuals, and 4 were diagnosed with suspected thyroid cancer with 2 cases confirmed with surgery. 

Confusing issues
Conducted every 2 years up to age 20, the TUE transitions at age 25 to milestone screenings to be conducted every 5 years. Some residents are beginning to participate in the age 25 milestone screening, and if they have never participated in the TUE, their milestone screening results will be added to the second round screening results. Thus the number of the second round screening participants is expected to increase even though the screening period technically ended in March 2016. 

However, the third round screening survey population excludes the age 25 milestone screening participants: their results will be tallied up separately.

Also in some cases, confirmatory examinations from the second and third rounds might be simultaneously ongoing, or there could be significant delays in conducting confirmatory examinations due to logistical issues such as the lack of manpower. A two-year screening period originally designed for subsequent rounds of the Full-Scale Screening is essentially spread over a longer time period, overlapping with the next round of screening. A precise interpretation of the results from each round of screening might be nearly impossible.

Newly diagnosed cases
The second round: Two cases were newly diagnosed by FNAC with suspicion of cancer. One is s a male from Iwaki City who was 12 years old at exposure or at the time of the March 2011 disaster. The other is a female also from Iwaki City who was 11 years old at exposure. 

The third round: Four cases were newly diagnosed by FNAC with suspicion of cancer. Two are from the evacuation area, and the other two are from Nakadori, the central part of Fukushima Prefecture. Two are males who were both age 10 at exposure, and two are females whose ages at exposure were 8 and 13.

Prior diagnostic status of the cases newly diagnosed with cancer
The second round: The first round screening results for the 2 new cases were A1 and A2. There was no mention of whether the A2 lesion was nodule or not. Of 71 total cases suspected or confirmed with cancer in the second round, 33 were A1, 32 were A2 (7 nodules, 24 other non-nodular lesions, and 1 unknown), and 5 were B (at least 2 having undergone the confirmatory examination) in the first round. One remaining case never underwent the first round screening (no information such as age, sex or place or residence, is available regarding this case).

The third round: Of 4 newly diagnosed cases, 3 were A2 (1 nodule, 2 other) and 1 was B in the second round.

This means at least 59 (33 "A1" and 26 "A2 other") of 75 cases (nearly 80%) had no nodules detected by ultrasound in the previous round which could have developed into cancer. At the last Oversight Committee meeting, Akira Ohtsuru, the head of the TUE called them "newly detected" rather than "newly formed." (See this post for further explanation). 

An issue of the female to male ratio
The female to male ratio of cancer cases warrants a special attention. For thyroid cancer, the female to male ratio is nearly 1:1 in the very young, but it is known to increase with age and decrease with radiation exposure. (See below Slide 2 in this post for more information). In the second round, the female to male ratio has been ranging from 1.19:1 to 1.44:1 overall, but the FY2015 municipalities have consistently shown a higher number of males than females with the most recent female to male ratio of 0.7:1.

What Ohtsuru said about the the female to male ratio is essentially the same as his statement at the last meeting, justifying the low female to male ratios observed in this population without concrete scientific evidence. (Refer to this post for details).

An issue of the participation rate
The participation rate is on steady decline in all age groups. 

The primary examination participation rate of 71.0% in the second round screening is lower than 81.7% in the first round. The third round, still actively ongoing, shows an overall participation rate of 35.8%, which increased by about 10% since the last report.

Most notable is the participation rate of the oldest age group: 52.7% for ages 16-18 (age at exposure) in the first round plummeted to 25.7% for ages 18-22 (age at examination) in the second round. It is 8.2% for ages 18-24 (age at examination) for the ongoing third round so far.

Younger age groups in school have maintained pretty high participation rates thanks to the school-based screening. The older age group often leave the prefecture for college or jobs, and it becomes increasingly difficult to get them to participate, especially with their interests fading in their busy lives. Fukushima Medical University (FMU) is conducting on campus screening at some colleges to boost the participation rate.

New: Reporting results by districts, not municipalities
For the first time, the third round results did not include the confirmatory examination results by individual municipalities as before but by four regions, 1) 13 municipalities in the evacuation zone (some municipalities only partially evacuated), 2) Nakadori (central region), 3) Hamadori (eastern, coastal region), and 4) Aizu (western region). As a result, regional data was reported on how many eligible residents actually participated in the confirmatory examination and eventually diagnosed with suspected or confirmed thyroid cancer.

Reasoning behind this, according to FMU, is to protect privacy and deter discrimination against those from smaller municipalities diagnosed with thyroid cancer. Ohtsuru backed up the new reporting format by explaining how medical data based on the national insurance claim are protected by not disclosing the number of cases in municipalities with population fewer than 2,000. Whether the TUE database should be treated like the national medical insurance database may be open for debate, but regional reporting of cancer cases is certainly not conducive to analysis by outside experts.

Unreported cases of thyroid cancer
This was the first Oversight Committee meeting since the unreported case of thyroid cancer came to light back in March. The issue was that only cancer cases directly diagnosed during the confirmatory examination are reported to the Oversight Committee. Some questionable cases undiagnosed during the confirmatory examination go on to be followed up under regular medical insurance. According to FMU that actually conducts the health survey, these "follow-up" cases are deemed outside the boundaries and responsibilities of the TUE, with no obligation or actual system to collect data for reporting. 

This disinclination apparently ticked off some committee members who learned of the unreported case from media reports. They expressed their strong beliefs about the need for reporting all cancer cases to the Oversight Committee, regardless of when, where, and how they are diagnosed. Shoichiro Tsugane, a committee and subcommittee member and Director of Research Center for Cancer Prevention and Screening at the National Cancer Center, went so far as saying, "All cancer cases from the survey population, regardless of whether they were diagnosed during the confirmatory examination or the follow up, must be included in the count for the data to be valid. Studies using incomplete data with missing counts cannot possibly be accepted internationally as scientific. It's merely a scientific rule."

By the way, Fukushima Prefecture actually has a way of gathering some clinical information through their TUE Support Program that reimburses out-of-pocket medical costs incurred from medical care of thyroid cancer and other conditions diagnosed during the TUE and followed in regular medical care. Applicants must be TUE participants not qualifying for public assistance for medical cost. They must submit some clinical information in exchange for receiving assistance. This allows Fukushima Prefecture to collect some information for surgeries and/or biopsies conducted at FMU as well as facilities not affiliated with the TUE. The TUE Support Program provided reimbursements to 192 individuals ages 18-24 in FY2015-2016, including 67 surgical cases (62 thyroid cancer cases and 5 non-cancer cases such as follicular adenoma). Of 62 thyroid cancer cases, 59 were diagnosed during the confirmatory examination and 3 were diagnosed during regular medical care either after going through or opting out of the confirmatory examination.

However, those younger than 18 are ineligible to apply for aid due to free medical care offered by Fukushima Prefecture. One such case, a male who was age 4 at the time of the accident and diagnosed with thyroid cancer during follow-up after the second round confirmatory examination, was discovered when the family applied for aid from the 311 Fund for Children with Thyroid Cancer (referred as the "311 Fund" hereafter). The 311 Fund is a private group distributing one-time aid of 100,000 yen (and an additional 100,000 yen for those undergoing radioiodine treatment) to eligible applicants. Applicants must be 25 or younger, residing in 16 prefectures including Tokyo at the time of the accident, and diagnosed with thyroid cancer after the 2011 Fukushima nuclear accident. Uniqueness and perhaps strength of the 311 Fund is that it does not exclude the TUE Support Program participants because the 311 Fund aims to offer a temporary financial relief for families with cancer patients that inevitably incur extra expenses from frequent visits to hospitals.

The status of the new third-party committee
The "international, third-party, neutral, scientific, up-to-date and evidence-based" expert committee proposed by Chairman Hokuto Hoshi at the 25th Oversight Committee meeting is no more.

It was revealed by a prefectural official that the Japanese government has decided to work with the already planned "international expert group" from the International Agency for Research on Cancer (IARC), a subsidiary of the World Health Organization (WHO) which is a specialized agency of the United Nations (UN).

Further elaborated by a committee member Tamami Umeda (Director General, Environmental Health Department, Ministry of the Environment), the new direction deviates from the original intent of the third-party committee—to offer the latest knowledge of thyroid cancer needed by the Oversight Committee, but nevertheless she was quite taken by it. The story, sounding almost too perfect, goes like this: 

As Umeda explores potential candidates for the proposed third-party committee and decides on a UN organization, she hears about IARC's upcoming international expert group that is planning an investigation on how to go about thyroid monitoring after nuclear emergencies. The IARC expert group will report their scientific findings back to policy makers and health officials of UN member nations. And the IARC expert group already plans on visiting Fukushima, the land full of information they seek. Purpose of the IARC expert group may not be to evaluate and analyze the results of the TUE, but the findings of such an authoritative organization must be useful to the Oversight Committee as well as the Thyroid Examination Assessment Subcommittee. So why not get on with them?

Umeda's presentation was a surprise, given the May 31, 2017 article in Fukushima Minpo (archived here) that announced the establishment of a new international expert committee—by Fukushima Prefecture and Ministry of the Environment—investigating causality between the nuclear accident and thyroid cancer. The Minpo article stated that selection of the committee members would be based upon recommendations from relevant academic societies within Japan as well as from international organizations specializing in radiation protection or medicine and health. Fukushima Prefecture was to explain about the plan at the June 5 Oversight Committee meeting. 

Only 5 days later, the plan had drastically changed. 

Curiously, Fukushima Prefecture's Yoichi Suzuki (Chief, Department of Health and Welfare, Section for Fukushima Health Management Survey) later admitted upon a citizen's inquiry that it wasn't Fukushima Prefecture that offered information published in the Minpo article.

A look back at how the idea of the third-party committee originally came about may offer a full circle, so to speak:

The third-party committee was recommended by the Organizing Committee of 5th International Expert Symposium in Fukushima on Radiation and Health, including infamous Shunichi Yamashita. The symposium featured Chernobyl researchers and speakers from various agencies and organizations—the lineup of usual suspects—such as the WHO, the IARC, International Atomic Energy Agency (IAEA), the United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR), the International Commission for Radiological Protection (ICRP), the National Council on Radiation Protection and Measurements (NCRP), Fukushima Medical University, Nagasaki University, etc. 

Proceedings from the symposium have recently been published as a book coedited by none other than Shunichi Yamashita and Geraldine Thomas. The book "encompasses authoritative data and interpretation of the thyroid screening program in Japan." 

A former chair to the Oversight Committee, Yamashita resigned from the position in March 2013 amid controversies surrounding "secret meetings." Although no longer involved with the Oversight Committee, he has maintained ties with the Survey as Founding Senior Director of the Radiation Medical Science Center for the Fukushima Health Management Survey, the Office of International Cooperation for the Survey.

Future committee/subcommittee member selection
It appears that future members of the Oversight Committee and the Thyroid Examination Assessment Subcommittee are to be selected from relevant organizations or academic societies with new additions of pediatric specialists, psychologists, thyroid clinicians, etc. Suggestions were made to include local pediatricians, medical ethicists, lawyers, and public members.

Notably, Kazuo Shimizu, a thyroid surgeon and current chair of the Thyroid Examination Assessment Subcommittee, declined to be appointed chair again so that he could express his professional opinions more freely.

Concluding remarks
This joint session of the Oversight Committee and the Thyroid Examination Assessment Committee depicted a continuing deterioration in quality and proceedings of the meeting as well as the press conference. 

May 2015 replacement of eloquently speaking Shinichi Suzuki with less articulate Ohtsuru in reporting on the TUE to the Oversight Committee led to disclosure of less and less information. This time, individual municipal data for the confirmatory examination was withheld by FMU, let alone acknowledgement about the unreported cancer cases. 

Incompleteness of the officially reported data presents a serious lack of transparency and is a breach of trust with the residents participating in the health survey. Yet there seems to be no systematic venue for the Oversight Committee to enforce a proper release of information on behalf of the residents. Simply, the Oversight Committee has failed. 

On few clinical details released, if any, Ohtsuru's explanations do not always add up as in the female to male ratio, for example. Here Ohtsuru is likely just a messenger who conveys opinions of experts from the quarterly Diagnostic Criteria Subcommittee of the weekly-held Thyroid Examination Expert Committee, both of which have a constant presence of Shunichi Yamashita. In essence, Yamashita has been behind the scene of the TUE all this time ever since his resignation from the post of the Oversight Committee chair in March 2013.

The Diagnostic Criteria Subcommittee has been holding a closed meeting prior to each Oversight Committee meeting, discussing the results ahead of time, practically acting as the "other" Thyroid Examination Assessment Subcommittee. No wonder there appeared to be no pressing need for the actual Thyroid Examination Assessment Subcommittee since the last session was held in March 2015.

Premature denial of the radiation effects on thyroid cancer in Fukushima is driving some to question the effectiveness of the TUE, possibly suggesting reducing its scale just when the latency period of thyroid cancer has passed. (See Ohtsuru et al.) Meanwhile, Suzuki, a thyroid surgeon, calls for the TUE to be continued on a long term. Discordance amongst the key players is palpable. What Suzuki must be witnessing in the clinical setting is precisely what should be shared and discussed at the Thyroid Examination Assessment Subcommittee. It is evidently reported and discussed by experts at the Diagnostic Criteria Subcommittee.

How IARC's international expert group on thyroid monitoring (note it's not on thyroid cancer specifically) plays into the status of the TUE remains to be seen. Track record of UNSCEAR—another United Nations agency—is not exactly dazzling when it comes to truly protecting the exposed population. In fact, any expert group or researcher investigating radiation exposure issues relating to the Fukushima nuclear accident, is inevitably biased from the start because their knowledge base of the official data and assumptions is biased.

One thing is clear: the compromised pursuit of truth continues to victimize Fukushima residents and others directly affected by the Fukushima nuclear disaster.


Below is the summary of the basic information from each round of screening.

First Round Screening (October 2011 - April 2015)
(This is the updated final results as of March 31, 2017).
The number of confirmed and suspected cancer cases remains the same, but some information has been corrected for duplicates.

Total number targeted: 367,649
Number of participants in primary examination: 300,473
Number with confirmed results: 300,473
  • A1   154,605 (51.5%) (no nodules or cysts found)
  • A2   143,574 (47.8%) (nodules ≦ 5.0 mm or cysts ≦ 20.0 mm)
  • B        2,293   (0.8%) (nodules ≧ 5.1 mm or cysts ≧ 20.1 mm)
  • C               1   (0.0%) (requiring immediate secondary examination)
(Note: Cysts with solid components are treated as nodules).

Number eligible for confirmatory (secondary) examination: 2,293
Number of participants in confirmatory (secondary) examination: 2,130
Number with confirmed results : 2,090
Number of fine-needle aspiration cytology (FNAC): 547
Number of cases suspicious or confirmed of malignancy: 116 (including one case of benign nodules)
Number with confirmed tissue diagnosis after surgery: 102
  • 1 benign nodule
  • 100 papillary thyroid cancer
  • 1 poorly differentiated cancer
Second Round Screening (April 2014 - March 2016) (see report here)
Total number targeted: 381,256
Number of participants in primary examination: 270,511
Number with confirmed results: 270,497
  • A1   108,697 (40.2%) (no nodules or cysts found)
  • A2   159,574 (59.0%) (nodules ≦ 5.0 mm or cysts ≦ 20.0 mm)
  • B        2,226   (0.8%) (nodules ≧ 5.1 mm or cysts ≧ 20.1 mm)
  • C               0   (0.0%) (requiring immediate secondary examination)
(Note: Cysts with solid components are treated as nodules).

Number eligible for confirmatory (secondary) examination: 2,226
Number of participants in confirmatory (secondary) examination: 1,832
Number with confirmed results : 1,748
Number of fine-needle aspiration cytology (FNAC): 200
Number of cases suspicious or confirmed of malignancy: 71
Number with confirmed tissue diagnosis after surgery: 49
  • 48 papillary thyroid cancer
  • 1 "other" thyroid cancer
Third Round Screening (May 2016 - March 2018) (see report here)
Total number targeted: 336,616
Number of participants in primary examination: 120,596
Number with confirmed results: 105,966
  • A1   36,928 (34.8%) (no nodules or cysts found)
  • A2   68,347 (64.5%) (nodules ≦ 5.0 mm or cysts ≦ 20.0 mm)
  • B          691  (0.7%) (nodules ≧ 5.1 mm or cysts ≧ 20.1 mm)
  • C             0   (0.0%) (requiring immediate secondary examination)
(Note: Cysts with solid components are treated as nodules).

Number eligible for confirmatory (secondary) examination: 691
Number of participants in confirmatory (secondary) examination: 332
Number with confirmed results : 225
Number of fine-needle aspiration cytology (FNAC): 11
Number of cases suspicious or confirmed of malignancy: 4
Number with confirmed tissue diagnosis after surgery: 2
  • 2 papillary thyroid cancer
Table 6. Cytology results (as of March 31, 2017) 
(including information from Appendix 6: Number of surgeries among cases with malignancy or suspicion of malignancy)

Second Round Screening

Third Round Screening

Age distribution (age at the time of the March 2011 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 ...