Clinicopathological Findings of Fukushima Thyroid Cancer Cases: October 2016

On September 26-27, 2016, the “5th International Expert Symposium in Fukushima on Radiation and Health: Chernobyl+30, Fukushima+5: Lessons and Solutions for Fukushima’s Thyroid Question” was held in Fukushima City. The symposium was organized by the Nippon Foundation, co-organized by Fukushima Medical University, Nagasaki University, and Hiroshima University, and supported by Fukushima Prefecture, Japan Medical Association, Japan Nursing Association, and Japan Pharmaceutical Association. Program PDF can be viewed here. Information on previous symposia can be found on the following web pages: 1st symposium, 2nd symposium, 3rd symposium, and 4th symposium.

The program featured the usual suspects from the pro-nuclear camp as some of the presenters who informed the audience that “Fukushima is different from Chernobyl” and emphasized the risk of overdiagnosis from cancer screening. This post focuses on clinical information for the surgical cases presented by Shinichi Suzuki, the thyroid surgeon at Fukushima Medical University in charge of the Thyroid Ultrasound Examination.

The last time Suzuki released such information was on August 31, 2015, and it was given in a narrative form on one sheet of paper (can be found here and translated here). This time it was given as a series of PowerPoint slides with more details than ever. Screenshots of some of the slides are shown below, accompanied by narrative explanations to put the information in context. Please note that this is neither the actual transcript of his presentation nor inclusive of all the slides shown during the presentation.

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“Childhood and Adolescent Thyroid Cancer after the Fukushima NPP Accident” by Professor Shinichi Suzuki, Fukushima Medical University (starts around 1:45:25 in the video embedded below, with Japanese interpretation).

http://www.ustream.tv/recorded/91672512

Note: Suzuki used the Thyroid Examination results released on June 6, 2016 with data as of March 31, 2016 during this presentation, although the new results as of June 30, 2016 were released on September 14, 2016.

Slide 1 

This presentation covers 125 cases of thyroid cancer that underwent surgeries at Fukushima Medical University between August 2012 and March 2016. During this time period, 132 cases underwent surgeries, 126 at Fukushima Medical University and 6 at other medical facilities. At Fukushima Medical University, 1 case was post-operatively diagnosed as a benign thyroid nodule, leaving 125 cancer cases. (Note: The August 2015 report stated 7 cases underwent surgeries at facilities other than Fukushima Medical University, but now it is 6 cases. No explanation was given regarding this discrepancy). 

As of March 31, 2016, 102 cases suspicious of cancer were operated from the first round (confirmed as 1 benign nodule and 101 cancer cases), while the second round yielded 30 cancer cases. Assuming the 6 cases operated at other medical facilities were from the first round, 125 cases presented here include 95 cases from the first round, leaving 30 cases to be accounted for by the second round.  It is not clear how many of the first round and the second round cases were actually operated at Fukushima Medical University. 125 presented here may not include 30 cases from the second round. (Note: Previous sentence was crossed out and a new sentence added on October 11, 2016). 

Slide 2

125 cases consisted of 44 males and 81 females, with the female-to-male ratio** of 1.8 to 1. 

Age at the time of the accident (i.e. age at exposure) ranged from 5 to 18 years, with an average age of 14.8 ± 2.7 years. Age at diagnosis ranged from 9 to 23, with an average age of 17.8 ± 3.1 years.

Location of tumor was ipsilateral (i.e. one-sided) in 121 cases (96.8%) and bilateral (i.e. on both sides) in 4 cases. In 121 ipsilateral cases, 67 were located in the right lobe, 53 in the left lobe, and 1 in the isthmus which connects together the lower thirds of the right and left lobes.

**Thyroid cancer is known to occur more commonly in females. The female to male ratio tends to increase with age. For instance, the female to male ratio in the 2009 US study is 4.3:1 with 94.5% of cases ≥ age 10 [1] . In the 1995 study of the cancer registry data from 1963 to 1992 in England and Wales, the female to male ratio was 1.25:1 in ages 5-9 and 3.1:1 in ages 10-14 [2]. The female to male ratio is also known to decrease in the radiation exposed cases. In the 2008 study that compared thyroid cancer cases (exposed to radiation) in Belarus, Ukraine and Russia after the Chernobyl accident with unexposed cases in the same region as well as in UK and Japan, the female to male ratio was 4.2:1 overall, 2.4:1 in age <10, 5.2:1 in age ≥10 in the unexposed cases, whereas the female to male ratio was 1.5:1 overall, 1.3:1 in age <10, and 1.6:1 in age ≥10 in the exposed cases [3].

Slide 3

TNM classification is explained below. Japan has its own clinical guidelines on cancers, but the TNM classification is essentially the same with the exception of the “Ex” notation which refers to the degree of extension outside the thyroid capsule: 
Ex1 means minimal extension (example: extension to sternothyroid muscle or perithyroid soft tissues) and is equivalent to T3.
Ex2 means further extension and is equivalent to T4.

Prefix “c” refers to “clinical” while “p” refers to “pathological.”

3 had distant metastases to the lungs. This is the first time that any clinical details of the distant metastasis cases are given.
1) Male. Age at exposure 16, age at surgery 19.
Pre-operative: cT3 cN1a cM1. Tumor size > 40 mm and limited to thyroid or any size with minimal extension outside the thyroid. Metastasis to lymph nodes in the central compartment of the neck. Distant metastasis.
Post-operative: pT3 pEx1 pN1a pM1. Tumor size > 40 mm and limited to thyroid or any size with minimal extension outside the thyroid. Minimal extension outside the thyroid. Metastasis to lymph nodes within the central compartment of the neck. Distant metastasis.
2) Male. Age at exposure 16, age at surgery 18.
Pre-operative: cT3 cN1b cM1. Tumor size > 40 mm and limited to thyroid or any size with minimal extension outside the thyroid. Metastasis to the neck lymph nodes outside the central compartment. Distant metastasis.
Post-operative: pT2 pEx0 pN1b pM1. Tumor size > 20 mm but ≤ 40 mm and limited to the thyroid. No extension outside the thyroid. Metastasis to the neck lymph nodes outside the central compartment. Distant metastasis.
3) Female. Age at exposure 10, age at surgery 13.
Pre-operative: cT1b cN1b cM1. Tumor size > 1 cm but ≤ 2 cm, limited to the thyroid. Metastasis to the neck lymph nodes outside the central compartment. Distant metastasis.

Post-operative: pT3 pEx1 pN1b pM1. Tumor size > 40 mm and limited to thyroid or any size with minimal extension outside the thyroid. Minimal extension. Metastasis to the neck lymph nodes outside the central compartment. Distant metastasis.

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TNM classification for differentiated thyroid cancer from the American Cancer Society website.

Primary tumor (T)

T indicates the size of the primary tumor and whether it has grown into the nearby area.

T1a: Tumor ≤ 1 cm, limited to the thyroid
T1b: Tumor > 1 cm but ≤ 2 cm in greatest dimension, limited to the thyroid
T2: Tumor size > 2 cm but ≤ 4 cm, limited to the thyroid
T3: Tumor size >4 cm, limited to the thyroid or any tumor with minimal extrathyroidal extension (eg, extension to sternothyroid muscle or perithyroid soft tissues)
T4a: The tumor is any size and has grown extensively beyond the thyroid gland into nearby tissues of the neck, such as the larynx (voice box), trachea (windpipe), esophagus (tube connecting the throat to the stomach), or the nerve to the larynx. This is also called moderately advanced disease.
T4b: The tumor is any size and has grown either back toward the spine or into nearby large blood vessels. This is also called very advanced disease.

Regional lymph nodes (N)
Regional lymph nodes are the central compartment, lateral cervical, and upper mediastinal lymph nodes:
N0: No regional lymph node metastasis
N1: Regional lymph node metastasis
N1a: Metastases to level VI (pretracheal, paratracheal, and prelaryngeal/Delphian lymph nodes)
N1b: Metastases to unilateral, bilateral, or contralateral cervical (levels I, II, III, IV, or V) or retropharyngeal or superior mediastinal lymph nodes (level VII)
Distant metastasis (M)
M0: No distant metastasis is found
M1: Distant metastasis is present

This slide is similar to Slide 3, except it describes why surgeries were conducted in 44 “cT1a cN0 cM0” cases with tumor ≤ 10 mm without any pre-operative clinical evidence of lymph node or distant metastases. (Surgery for thyroid “microcarcinoma,” i.e. cancer ≤ 10 mm, is controversial in adults).

11 of 44 cases underwent surgeries despite the recommendation of non-surgical, observational follow-ups. Remaining 33 cases had suspicion for one or more of the following conditions:

20 cases: Ex1 or Ex2 (extension beyond the thyroid capsule)

3 cases: N1a (metastases to lymph nodes within the central compartment of the neck)

10 cases: Invasion of the recurrent laryngeal nerve

7 cases: invasion of the trachea

1 case: Graves disease
1 case: Ground-glass opacity (GGO) of the lungs

 

Slide 5

This slide shows the post-operative findings of 44 “cT1a cN0 cM0” cases with tumor smaller than 10 mm without any pre-operative clinical evidence of lymph node or distant metastases described in Slide 4.

Of 11 cases that underwent surgery against the recommendation of non-surgical, observational follow-ups, 2 cases turned out to be pT1a pN0 pEx0, meaning the tumor was ≤ 10 mm without any regional lymph node involvement or extension beyond the thyroid capsule.

Of remaining 33 cases that had indications for surgery as described in Slide 4, 3 cases turned out to be pT1a pN0 pEx0.

Overall, 5 of 44 cases with tumor size ≤ 10 mm turned out to have no lymph node involvement or extension beyond the thyroid capsule, suggesting these 5 cases might not have actually needed surgery at the time. But this is in hindsight, and it should be remembered 33 cases originally did have clear surgical indications. (Curiously, the previous report from August 2015 states this number was “8.” No explanation was given by Suzuki as to the discrepancy. However, his admittance of “a few percent of recurrence” might allow for speculation that 3 of 8 cases recurred and no longer was classified “pT1a pNO pEx0.” It should be noted this has not been confirmed by Suzuki. It is expected he might discuss clinical details such as the recurrence rate during his presentation on the Thyroid Examination at the Annual Meeting of the Japan Thyroid Association on November 13-15, 2016, in Tokyo.

 

Slide 8

This slide shows the types of thyroid cancer found in 125 cases. 121 had papillary thyroid cancer (PTC), 3 had poorly differentiated thyroid cancer, and 1 had “other” thyroid cancer.

It should be noted that 2 of 3 cases of poorly differentiated thyroid cancer has since been reclassified as papillary thyroid cancer with unspecified subtypes in accordance with the revision of the thyroid cancer clinical guidelines (see this post for more information).

Regarding one case of “other” thyroid cancer, it was previously explained by Akira Ohtsuru, head of the Thyroid Examination, that the patient had differentiated thyroid cancer that is not considered to be related to radiation and categorized as “other” according to the classification in the seventh revision of Japan’s unique thyroid cancer diagnostic guidelines released in November 2015.

121 cases of papillary thyroid cancer showed 4 subtypes/variants:

110 cases of classical type

4 cases of follicular variant*

3 cases of diffuse sclerosing variant

4 cases of cribriform-morular variant**

A special notation was made by Suzuki that no solid variant of PTC–the most common subtype in Chernobyl–was seen. This is one of the claims repeated by the officials to emphasize the Fukushima cancer cases are unlike those in Chernobyl, i.e. unlikely to be due to the radiation effects. However, solid variant PTC is not exclusive to radiation-induced thyroid cancer, and a high frequency of solid variant PTC observed in Chernobyl might be due to the young age of the early cases [5,6,7]. Moreover, in one study, solid variant was not seen in Japanese childhood PTC [8].

*Recently, encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC) was reclassified as “noninvasive follicular thyroid neoplasm with papillary-like nuclear features” (NIFTP) [9]. However, cases of the follicular variant of papillary thyroid cancer found here are not assumed to be EFVPTC since they were never reclassified as non-cancer. This subject never came up during the Oversight Committee meetings.

**Cribriform-morular variant is usually associated with familial adenomatosis polyposis.

Slide 9
This slide shows algorithms for diagnosis and treatment of papillary thyroid cancer according to the Japanese clinical guidelines.

Slide 10
This slide shows a comparison of surgical methods between Belarus and Fukushima. Most cases in Fukushima underwent hemithyroidectomy or lobectomy, whereas total thyroidectomy was the most common surgical method in Belarus.

Suzuki mentioned that extra care has been taken to reduce complications from surgeries, and hemithyroidectomy was employed when possible to decrease the lifetime need for thyroid hormone supplementation. Also, this article by Japan’s top thyroid surgeons states, “At present, Western countries adopted almost routine total thyroidectomy with radioactive iodine (RAI) ablation, while limited thyroidectomy with extensive prophylactic lymph node dissection has traditionally been performed for most patients in Japan.(…) In Japan, however, limited thyroidectomy such as subtotal thyroidectomy and lobectomy with isthmectomy has been traditionally adopted as the standard. This is partially because the capacity to perform RAI therapy is limited due to legal restrictions, and RAI therapy is not considered cost effective by the healthcare system in Japan. [10]”

Slide 11
This slide shows the genetic mutation profile in different study groups. 63.2% of 52 cases from Fukushima was shown to have BRAF mutation. In the 2015 study by Mitsutake et al.[11] shown in the green box, 43 (63.2%) of 68 cases are shown to be positive for BRAF V600E point mutation. The same study also shows 10.3% was positive for RET/PTC rearrangements (6 cases of RET/PTC1 and 1 case of RET/PTC3) and 4 cases (5.9%) had ETV6/NTRK3 rearrangement. (It’s unclear where “n=52” and 8.8% of TRK fusion came from for the Fukushima column, as the Mitsutake study has n=68 and did not test for TRK fusion. It’s also unclear where the Japanese adult data came from. Literature search revealed the BRAF frequency in PTC of Japanese adults varied in a wide range: 28.8% [12], 38.2% [13], 38.4% [14] , 53% [15], and 82.1% [16]).

The official stance is that the genetic alterations observed in Fukushima cases are similar to what is seen in typical adult papillary thyroid cancer and “probably reflects genetic status of all sporadic and latent thyroid carcinomas in the young Japanese population [11].” In other words, the official assert that the genetic profile appears consistent with the official claim that screening is diagnosing spontaneous and latent cancers which might not have been detected without screening.

However, literature varies in regards to how the genetic mutations are associated with radiation exposure, age, and iodine status. RET/PTC rearrangements, frequently seen in Chernobyl, are associated with both radiation-induced and spontaneous thyroid cancer [17], more common at younger age and in iodine deficient areas [18]. BRAF mutation is known to be seen more frequently in older age, but recent studies showed BRAF V600E was present in 36.8% (median age 13.7 years) [19] and 63% (median age 18.6 years) [20] of pediatric papillary thyroid carcinoma. BRAF mutation were associated with high iodine intake in China [21], while no difference in BRAF V600E frequency was found between iodine-rich and iodine-deficient countries recently [16].

Slide 12

This slide shows a graph with age distribution of thyroid cancer patients in Ukraine and Fukushima in different post-accident time periods, compiled by superimposing 2 graphs from Letter to the Editor of Thyroid [21]. Blue bars are for 1986-1990 in Ukraine (first 4 years after the Chernobyl accident) and red bars are for 2011-2013 in Fukushima (first 3 years after the Fukushima accident), both time periods representing “latency” for radiation-induced thyroid cancer in children. Orange bars are for 1990-1993 in Ukraine–after the latency period–showing a large increase in thyroid cancer cases in Ukrainian residents who were 18 or younger when the accident happened. Increased number of cases in those who were age 5 or younger set this time period apart. The year 1990 is also when large-scale screening programs began, initiated by international organizations [22].

The age distribution is “strikingly similar” between the first 4 post-accident years in Ukraine (blue bars) and the first 3 years in Fukushima (red bars), as acknowledged by the letter. However, the letter is inconsistent in claiming “if thyroid cancers in Fukushima were due to radiation, more cases in exposed preschool-age children would have been expected” and defining the first 4 years as “latency.” This illogical claim is also seen in a slightly different format as a comparison between different post-accident periods [23].

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Classification of cervical lymph nodes by the Japanese clinical guidelines

I: Prelaryngeal nodes: LN anterior to the thyroid cartilage and the cricoid cartilage
II: Pretracheal nodes: LN anterior to trachea, dissectible posteriorly from the inferior border of thyroid
III: Paratracheal nodes: LN lateral to trachea, extending inferiorly to where it is dissectible from the neck and superiorly where recurrent laryngeal nerve enters trachea.
IV: Prethyroid nodes: LN adjacent to anterior and lateral parts of thyroid. Laterally includes LN attached to thyroid when middle thyroid artery is ligated and cut. (Equivalent to the AJCC Level IV: lower jugular nodes)
(I, II, III and IV are equivalent to the AJCC Level VI: anterior compartment LN)
V: Superior internal jugular nodes: LN along internal jugular vein but superior to the inferior border of cricoid cartilage. This is further subdivided into superior and inferior at the bifurcation of common carotid artery
Va LN: inferior to the bifurcation of common carotid artery (equivalent to the AJCC Level II: upper jugular nodes)
Vb LN: superior to the bifurcation of common carotid artery (equivalent to the AJCC Level III: middle jugular nodes)
VI: Inferior internal jugular nodes: LN along internal jugular vein, inferior to the inferior border of cricoid cartilage. Includes LN in supraclavicular fossa.
VII: Posterior triangle nodes: LN located in posterior triangle bordered by anterior border of sternocleidomastoid muscle, posterior border of trapezius muscle, and omohyoid muscle.
VIII: Submandibular nodes: LN in the submandibular triangle.
IX: Submittal nodes: LN in the submental triangle.
(VIII and IX are equivalent to the AJCC Level I)
X: Superficial cervical  nodes: LN superficial to superficial layer of the deep cervical fascia enclosing sternohyoid and sternocleidomastoid muscles.
XI: Superior mediastinal nodes: LN unresectable by neck dissection
(Equivalent to the AJCC Level VII: superior mediastinal nodes)

References
[1] Hogan AR, Zhuge Y, Perez EA, Koniaris LG, Lew JI, Sola JE. Pediatric thyroid carcinoma: incidence and outcomes in 1753 patients. J Surg Res. 2009 Sep;156(1):167-72. doi: 10.1016/j.jss.2009.03.098.
[2] Harach HR, Williams ED. Childhood thyroid cancer in England and Wales. British Journal of Cancer. 1995;72(3):777-783.
[3] Williams ED, Abrosimov A, Bogdanova T, et al. Morphologic Characteristics of Chernobyl-Related Childhood Papillary Thyroid Carcinomas Are Independent of Radiation Exposure but Vary with Iodine Intake. Thyroid. 2008;18(8):847-852. doi:10.1089/thy.2008.0039.
[4] Robbins K, Clayman G, Levine PA, et al. Neck Dissection Classification Update: Revisions Proposed by the American Head and Neck Society and the American Academy of Otolaryngology–Head and Neck Surgery. Arch Otolaryngol Head Neck Surg. 2002;128(7):751-758. doi:10.1001/archotol.128.7.751.
[5] Ory C, Ugolin N, Schlumberger M, Hofman P, Chevillard S. Discriminating Gene Expression Signature of Radiation-Induced Thyroid Tumors after Either External Exposure or Internal Contamination. Genes. 2012;3(1):19-34. doi:10.3390/genes3010019.

[7] LiVolsi, VA, et al. The Chernobyl Thyroid Cancer Experience: Pathology. Clinical Oncology. 23(4):261-267.
[8] Williams ED, Abrosimov A, Bogdanova T, et al. Morphologic Characteristics of Chernobyl-Related Childhood Papillary Thyroid Carcinomas Are Independent of Radiation Exposure but Vary with Iodine Intake. Thyroid. 2008;18(8):847-852. doi:10.1089/thy.2008.0039.
[9] Nikiforov YE, Seethala RR, Tallini G, et al. Nomenclature Revision for Encapsulated Follicular Variant of Papillary Thyroid Carcinoma: A Paradigm Shift to Reduce Overtreatment of Indolent Tumors. JAMA Oncol. 2016;2(8):1023-1029. doi:10.1001/jamaoncol.2016.0386.

October 14, 2016 Posted by dunrenard | Fukushima 2016 | Fukushima continuing, Thyroid Cancers | 1 Comment

President of Fukushima Pediatric Association recently hand delivered the Association’s requests to Fukushima Prefecture to “scale down” thyroid exams for children in Fukushima

Does Fukushima Prefecture need to scale down or expand its existing thyroid exams provided to Fukushima children who were 18 years of younger at the time of Fukushima nuclear accident in 2011?

President of Fukushima Pediatric Association recently hand delivered the Association’s requests to Fukushima Prefecture to “scale down” thyroid exams for children in Fukushima.

Fukushima Pediatric Association claims that identifying many children with thyroid cancer through Prefecture’s thyroid exams is causing anxiety among children, their guardians, and citizens in the prefecture, and requests that a partial re-consideration of the thyroid exam is necessary.

(By the way, can you tell which one is Dr. Kazuhiro Ohga of Fukushima Pediatric Association and which one is an official of Fukushima Prefecture, just by looking at the photo of the article? I initially thought the man on the right is an official from the Fukushima Prefecture, because the man on left is bowing deeper, as if he is asking a favor by delivering a request. I was wrong. Dr. Ohga is on the right.)

http://this.kiji.is/141480622388215816?c=39546741839462401

On the other hand, a citizens’ group with parents of children whose thyroid cancers were detected because of Prefecture’s thyroid exams requests Fukushima Prefecture to expand the exams.

http://ourplanet-tv.org/?q=node%2F2057

Credit to Mari Inoue

August 26, 2016 Posted by dunrenard | Fukushima 2016 | Fukushima continuing, Thyroid Cancers | Leave a comment

【Thyroid Cancer in Fukushima】Fukushima Thyroid Examination Under Dual Review

Monday, August 8, 2016

Below is unofficial translation of two Fukushima Minyu articles regarding the review of the thyroid examination, published on August 8, 2016 and July 4, 2016. The August article is based on an interview of Hokuto Hoshi, Chair of Oversight Committee for the Fukushima Health Management Survey. It might be tied to this post. The July article covers the launch of an independent exploratory committee by Fukushima Pediatric Association.

Interestingly, a telephone inquiry by a concerned citizen revealed the Division of the Fukushima Health Management Survey at the Fukushima Prefectural Office was unaware of the content of the August article before its publication in newspaper. They declined to comment on the issue for the time being while contacting Oversight Committee Chair Hoshi to confirm facts and discuss the issue internally.

On September 26-27, 2016, the 5th International Expert Symposium “Chernobyl+30, Fukushima+5: Lessons and Solutions for Fukushima’s Thyroid Question” will be held in Fukushima, organized by Nippon Foundation and co-organized by Fukushima Medical University, Nagasaki University and Sasakawa Memorial Health Foundation. Judging from the symposium theme, there seems to be a rush to bring closure to the thyroid cancer issue even before the final results of the second round screening are released. A glance at the program is quite revealing.

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Oversight Committee for the Fukushima Health Management Survey Plan to Review the Thyroid Examination: Reduction in Target Population Considered

August 8, 2016

Oversight Committee for the Fukushima Health Management Survey, engaged in discussion on the status of the survey to examine the health effects due to the nuclear accident, will begin discussions as early as September to consider reduction in target population as well as review of the screening procedure.

The thyroid examination that targets all residents who were age 18 or younger at the time of the accident will face a big turning point, as revealed by the Oversight Committee Chair Hokuto Hoshi in the interview with Fukushima Minyu as of August 7th.

The thyroid examination targets about 380,000 residents. Thyroid cancer cases detected by the examination are considered “unlikely to be the effect of radiation exposure at this time” by the Oversight Committee.

What lies behind starting the discussion to consider review of the examination is the concern about detection of “latent cancer” cases, which exist at a constant rate regardless of radiation exposure, by screening with high sensitivity.

Thyroid cancer is curable in many cases, and the across-the-board cancer screening is unlikely to give rise to the merit of “reduced mortality.” Thus thyroid cancer screening is not globally recommended. This has led medical providers to voice concerns that “participation in the examination alone can be detrimental to the participants.”

Under the circumstance, the Oversight Committee is expected to begin discussions on issues such as: 1) Whether residents older than age 18 should be included in the target population in the future; and 2) Whether to change the method of mass screening currently conducted in school settings which has been pointed out to interfere with the participant’s wish not to participate.

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“Thyroid Examination” Should Be Reviewed: Fukushima Pediatric Association to Establish an Independent Committee

July 4, 2016

Fukushima Pediatric Association (president: Kazuhiro Ohga) adopted a general assembly statement incorporating the establishment of its own exploratory committee to consider the status of the thyroid examination on July 3, 2016 at the general meeting held in Kooriyama City. The thyroid examination, part of the Fukushima Health Management Survey that investigates health effects of the Tokyo Electric Fukushima Daiichi nuclear power plant accident, is conducted by the prefecture targeting residents who were age 18 or younger at the time of the accident. The association deems necessary to review the thyroid examination, taking a fresh look at part of it. This is the first time the association expresses the need to review the examination.

Five years have passed since the nuclear accident, a question was raised about the status of the thyroid examination mainly by pediatricians performing medical examinations on residents who are targeted for the thyroid examination.

According to the Fukushima Pediatric Association, there are 172 individuals (as of the end of March 2016) who have been diagnosed with thyroid cancer or “suspicion of cancer.” Thyroid cancer is curable in many cases, and the screening is unlikely to give rise to the merit of “reduced mortality,” while there is a mental detriment when diagnosed with cancer. Thus thyroid cancer screening is not globally recommended.

The general assembly statement referred to health worries experienced by children participating in the thyroid examination and their guardians as well as residents, stating “It is necessary to explain (the results) to the participants with care and compassion and offer an easily comprehensible explanation to residents.”

President Ohga stated, “The thyroid examination was started in order to alleviate anxiety of residents, but it is possible the examination created (new) anxieties. It is necessary to review the examination from the standpoint of the participants.”

The Exploratory Committee, comprising the association members, is scheduled to begin discussions this fall. It will take up opinions of those diagnosed with thyroid cancer and intend to set directions before next year’s general assembly. In addition, the content of the general assembly statement will be sent to the prefectural government as a request in the future.

The statement also incorporates items regarding the response to health effects on children, long-term health management, and continuing support for children and their families who are evacuated or returning.

August 22, 2016 Posted by dunrenard | Fukushima 2016 | Fukushima continuing, Thyroid Cancers | Leave a comment

30 Fukushima children diagnosed with thyroid cancer in second check but radiation said ‘unlikely’ cause

30 Fukushima children diagnosed with thyroid cancer in second check but radiation said ‘unlikely’ cause

FUKUSHIMA – In a study that began in April 2014 to check the impact of the 2011 Fukushima reactor meltdowns, 30 children have so far been diagnosed with thyroid cancer and 27 others are suspected of having the disease, according to a prefectural government panel.

Most of them were thought to be problem-free when their thyroid glands were checked during the first round of the study conducted over a three-year period through March 2014, the panel said Monday.

The first survey covered about 300,000 people who were under the age of 18 and living in Fukushima Prefecture when the nuclear disaster was triggered by the 3/11 earthquake and tsunami.

The number of children diagnosed with thyroid cancer in the second round was up from 16 as reported at the previous panel meeting in February.

Hokuto Hoshi, head of the panel and a senior member of the Fukushima Medical Association, maintained his earlier view of the correlation between the cancer figures and radiation, saying based on expertise acquired so far, it is “unlikely” that the disease was caused by radiation exposure.

Hoshi also said: “Concerns have been growing among Fukushima residents with the increase in the number of cancer patients. We’d like to further conduct an in-depth study.”

When the results of the first and the ongoing second round of the heath study are combined, the number of children diagnosed with thyroid cancer totals 131, and 41 others are suspected of having it.

According to Fukushima Medical University and other entities involved in the health checks, the 57 children in the second round of the survey either confirmed or suspected to have thyroid cancer were age 5 to 18 when the crisis started, and the sizes of their tumors ranged from 5.3 mm to 35.6 mm.

The examiners were able to estimate how much external radiation exposure 31 of those children had over the four months immediately after the catastrophe started, with the maximum being 2.1 millisieverts. Eleven of the children were exposed to less than 1 millisievert.

http://www.japantimes.co.jp/news/2016/06/07/national/30-fukushima-children-diagnosed-with-thyroid-cancer-in-second-check-but-radiation-said-unlikely-cause/#.V1ZpJde1xlK

June 7, 2016 Posted by dunrenard | Fukushima 2016 | Fukushima continuing, Thyroid Cancers | Leave a comment

Fukushima medical survey confirms 14 new child thyroid cancer cases

The 131 number of child thyroid cancers mentioned in this article is wrong.

As of today 173 people diagnosed with thyroid cancer in Japan’s Fukushima

The number of child thyroid cancers discovered in the wake of the Fukushima nuclear disaster has reached 131, with the latest panel review adding 14 to the list of those suffering from the deadly disease, along with dozens of new suspected cases.

After the latest review of the ongoing second round of medical checkups conducted on almost 300,000 children who were aged 18 or younger at the time of the accident at the Fukushima Daiichi plant in March 2011, the prefecture-run program announced that a total 131 people have now been diagnosed with thyroid cancer.

Some 30 thyroid cancer cases were added to the radiation victims toll following the second round of checkups that began in April 2014. A further 27 people are suspected of having the disease. Previous numbers disclosed in February showed that 16 patients suffered from cancer.

In the latest announcement, scientists also say that a child who was less than five-years-old at the time of the tragedy had also been diagnosed with cancer. The new figures of those confirmed or suspected to have thyroid cancer have tumors ranging from 5.3 mm to 35.6 mm.

The first thyroid cancer detection round studying minors was conducted in Japan between 2011 to 2014 and discovered 101 people with thyroid cancer. With the latest numbers, the new toll stands at 131, while another 41 are suspected of suffering from radiation exposure, Japan Times reports.

“Concerns have been growing among Fukushima residents with the increase in the number of cancer patients. We’d like to further conduct an in-depth study,” said Hokuto Hoshi, head of the panel and a senior member of the Fukushima Medical Association.

He however maintained the panel’s earlier accession that it is “unlikely” that the disease cases was caused by radiation exposure, reiterating claims that there is no direct link between thyroid cancer and the nuclear disaster.

After the earthquake and tsunami in March 2011, radioactive elements were released from the Fukushima Daiichi Nuclear Power Plant. After the release, Fukushima Prefecture continued to conduct thyroid screening ultrasounds on all residents agds 18 years and younger. The first round of screening included 298,577 examinees, while the round that began in April 2014 focuses on 267,769 people.

https://www.rt.com/news/345641-fukushima-child-thyroid-cancer/

June 7, 2016 Posted by dunrenard | Fukushima 2016 | Fukushima continuing, Thyroid Cancers | Leave a comment

Response to the Chicago Tribune Editorial “The children of Fukushima: When medical tests mislead”

The following is the letter to the Editor for the Chicago Tribune editorial, “The children of Fukushima: When medical tests mislead.” The letter was submitted through the online form on April 19, 2016, but there has been no response from Chicago Tribune. (Brevity of the content is due to the 400-word limit for letters).

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Dear Editor,

The March 25, 2016 Chicago Tribune editorial, “The children of Fukushima: When medical tests mislead” is misleading on its own regarding the childhood thyroid cancer situation in Fukushima Prefecture, Japan.

Differences in cancer rates by distance from the accident site and contamination levels may not be obvious, but an epidemiological analysis by Tsuda et al. (http://journals.lww.com/epidem/Fulltext/2016/05000/The_Authors_Respond.37.aspx) found a dose response tendency with proximity to the accident site after adjusting for the length of time between the accident and the time of screening. It is also important to remember only 1,080 children had their thyroid exposure doses directly measured and that is only 0.36% of 300,000 children who underwent thyroid ultrasound examination. Taken under high background levels, the doses are far from being accurate.

Children younger than age 5 showed an increased rate of thyroid cancer beginning at 4-5 years after the Chernobyl accident, so the first 3 years after the Fukushima accident, covered by the completed first round screening, would not expect to see that age group affected. The first cancer case was diagnosed about 17 months after the accident, not within a year, and some of these early cases might have been the result of radiation exposure promoting the growth of latent cancer that might not have become large enough to be detected until much later in life if unexposed to radiation.

Comparison with three other prefectures where one cancer case was diagnosed in 4,365 subjects is invalid as its small sample size lacks the necessary statistical power. The Korean screening is in adults and should not be compared with children.

It is true that unnecessary medical testing can lead to overdiagnosis and overtreatment, but the clinical information provided by Fukushima Medical University, such as metastasis and physical proximity of tumor to other vital structures, validates surgical interventions for the majority of the operated cases in Fukushima. Thyroid cancer is believed to grow slowly, but 80% of thyroid cancer cases discovered in the ongoing second round screening had no suspicious findings in the first round screening only 2-3 years earlier.

It is not just a cancer death but cancer diagnosis itself that is concerning for patients and their loved ones, and the causality should not be prematurely prejudged. A lesson of the Fukushima children may be the importance of conducting a timely and adequate collection of the exposure data and a comprehensive evaluation of data in a transparent and unbiased manner.

Yuri Hiranuma, D.O.
Member, Radiation and Health Committee
Physicians for Social Responsibility

http://fukushimavoice-eng2.blogspot.fr/2016/05/response-to-chicago-tribune-editorial.html

May 23, 2016 Posted by dunrenard | Fukushima 2016 | Fukushima continuing, Thyroid Cancers | Leave a comment