Regional Distribution of Fukushima Thyroid Cancer Cases (Confirmed and Suspected) Analyzed by Citizen Scientists

The first round of thyroid examination concluded in March 2014, and its results are nearly complete, except for some of the secondary examination results which were still not available as of August 24, 2014. Fukushima Medical University denies any regional difference in the incidence of thyroid cancer amongst Fukushima children and considers it unlikely that the current incidence of cancer is related to radiation exposure.  Although it might not be possible to epidemiologically assess the radiation health effects until the second round of thyroid examination is finished at the end of March 2016, the currently available data could still be analyzed in more detail.

As the nature of Japanese language allows significant amounts of information to be shared in a tweet using 140 letters, there has been an active discussion going on regarding the thyroid examination results on Twitter. When the results are released by Fukushima Medical University, citizen scientists--some professionals and some concerned citizens--would closely examine and analyze them.

Some say it is all due to the screening effect, having nothing to do with radiation exposure, and they claim the thyroid examination is causing more harm by unearthing cancer that might have laid dormant until much later in life. Some go to the other extreme to claim all the cancer cases could be due to radiation exposure. And there are those who are somewhere in-between, calling for a careful data collection and analysis so as not to miss any cases which might potentially be related to radiation exposure.

Two of the Twitter users actively involved in the discussion, @pririn and @iPatrioticmom, analyzed the latest Fukushima thyroid ultrasound examination results, released n August 24, 2014. Rather than claiming definite radiation health effects, which at this point is difficult to do, they simply want to point out the need for proper analyses of data from the first round of examination. They admit that this analysis is not by any means a final one and that the data is not age adjusted.

The translation was assisted by @sitesirius and @niigatamama.

Original analysis in an Excel file: Japanese and English.


Tab 1: Regional distribution of confirmed and suspected thyroid cancer cases in 
Fukushima Prefecture

Based on Table 8 of "Thyroid Examination (Initial Screening)" provisional results

	FY2011 target municipalities
	FY2012 target municipalities
	FY2013 target municipalities

No.	City, Town, Village		Number of primary examination participants	Number of confirmed or suspected cancer	Proportion of confirmed or suspected cancer	Incidence per 100,000
1	Minamisoma	南相馬市	10789	2	0.02%	19
2	Date	伊達市	10606	2	0.02%	19
3	Tamura	田村市	6327	3	0.05%	47
4	Kawamata	川俣町	2221	2	0.09%	90
5	Namie	浪江町	3249	2	0.06%	62
6	Hirono	広野町	838	0	0.00%	0
7	Naraha	楢葉町	1153	0	0.00%	0
8	Tomioka	富岡町	2302	1	0.04%	43
9	Okuma	大熊町	1973	1	0.05%	51
10	Futaba	双葉町	949	0	0.00%	0
11	Iitate	飯舘村	943	0	0.00%	0
12	Kawauchi	川内村	280	1	0.36%	357
13	Katsurao	葛尾村	183	0	0.00%	0
	Subtotal	計	41813	14	0.03%	33.5
14	Fukushima	福島市	47336	12	0.03%	25
15	Koori	桑折町	1857	0	0.00%	0
16	Kunimi	国見町	1429	0	0.00%	0
	Subtotal	計	50622	12	0.02%	23.7
17	Nihonmatsu	二本松市	8846	5	0.06%	57
18	Motomiya	本宮市	5233	3	0.06%	57
19	Koriyama	郡山市	53962	23	0.04%	43
20	Shirakawa	白河市	10805	6	0.06%	56
21	Miharu	三春町	2717	1	0.04%	37
22	Otama	大玉村	1372	2	0.15%	146
23	Ten-ei	天栄村	878	0	0.00%	0
24	Nishigo	西郷村	3618	1	0.03%	28
25	Izumizaki	泉崎村	1156	1	0.09%	87
	Subtotal	計	88587	42	0.05%	47.4
26	Soma	相馬市	5046	0	0.00%	0
27	Shinchi	新地町	1105	0	0.00%	0
	Subtotal	計	6151	0	0.00%	0
28	Iwaki	いわき市	47759	19	0.04%	40
	Subtotal	計	47759	19	0.04%	39.8
29	Sukagawa	須賀川市	11532	4	0.04%	35
30	Kagamiishi	鏡石町	1947	0	0.00%	0
31	Yabuki	矢吹町	2452	0	0.00%	0
32	Ishikawa	石川町	2078	1	0.05%	48
33	Yamatsuri	矢祭町	774	0	0.00%	0
34	Asakawa	浅川町	1067	0	0.00%	0
35	Tanagura	棚倉町	2256	1	0.04%	44
36	Hanawa	塙町	1210	0	0.00%	0
37	Ono	小野町	1317	0	0.00%	0
38	Furudono	古殿町	790	0	0.00%	0
39	Nakajima	中島村	801	0	0.00%	0
40	Hirata	平田村	824	1	0.12%	121
41	Samegawa	鮫川村	503	0	0.00%	0
42	Tamakawa	玉川村	984	0	0.00%	0
	Subtotal	計	28535	7	0.03%	24.5
43	Kitakata	喜多方市	5710	0	0.00%	0
44	Aizuwakamatsu	会津若松市	14632	5	0.03%	34
45	Minamiaizu	南会津町	1803	0	0.00%	0
46	Kaneyama	金山町	136	0	0.00%	0
47	Mishima	三島町	129	0	0.00%	0
48	Shimogo	下郷町	688	1	0.15%	145
49	Nishiaizu	西会津町	638	0	0.00%	0
50	Tadami	只見町	492	0	0.00%	0
51	Inawashiro	猪苗代町	1871	1	0.05%	53
52	Bandai	磐梯町	413	0	0.00%	0
53	Aizumisato	会津美里町	2547	0	0.00%	0
54	Aizubange	会津坂下町	2074	1	0.05%	48
55	Yanaizu	柳津町	375	0	0.00%	0
56	Hinoemata	檜枝岐村	61	0	0.00%	0
57	Showa	昭和村	101	0	0.00%	0
58	Kitashiobara	北塩原村	382	0	0.00%	0
59	Yugawa	湯川村	507	1	0.20%	197
	Subtotal	計	32559	9	0.03%	27.6

■ Incidence rate in adjacent municipalities, grouped together so each group consists of about 10,000 to 20,000 primary examination participants (age group is not controlled)

(Groups are shown in gradations of the color--blue, yellow, or green--assigned to each fiscal year's target municipalities in the table above).

■ Regional differences--up to 5 times between the FY2012 and FY2013 target municipality groups as shown below:

FY2012 Nihonmatsu, Motomiya and Otama, 64.7 per 100,000 (shown in red)

FY2013 Northern Hamadori and Southern Nakadori, 13.0 per 100,000 (shown in green--top and bottom of the map)

*****

Shown below is the same table as above, except with each fiscal year's target municipalities color-coded according to the map immediately below. Names of the municipalities are shown in English and numbers are assigned corresponding to the numbers shown in the leftmost column.

	FY2011 target municipalities
	FY2012 target municipalities
	FY2013 target municipalities

No.	City, Town, Village		Number of primary examination participants	Number of confirmed or suspected cancer	Proportion of confirmed or suspected cancer	Incidence per 100,000
1	Minamisoma	南相馬市	10789	2	0.02%	19
2	Date	伊達市	10606	2	0.02%	19
3	Tamura	田村市	6327	3	0.05%	47
4	Kawamata	川俣町	2221	2	0.09%	90
5	Namie	浪江町	3249	2	0.06%	62
6	Hirono	広野町	838	0	0.00%	0
7	Naraha	楢葉町	1153	0	0.00%	0
8	Tomioka	富岡町	2302	1	0.04%	43
9	Okuma	大熊町	1973	1	0.05%	51
10	Futaba	双葉町	949	0	0.00%	0
11	Iitate	飯舘村	943	0	0.00%	0
12	Kawauchi	川内村	280	1	0.36%	357
13	Katsurao	葛尾村	183	0	0.00%	0
	Subtotal	計	41813	14	0.03%	33.5
14	Fukushima	福島市	47336	12	0.03%	25
15	Koori	桑折町	1857	0	0.00%	0
16	Kunimi	国見町	1429	0	0.00%	0
	Subtotal	計	50622	12	0.02%	23.7
17	Nihonmatsu	二本松市	8846	5	0.06%	57
18	Motomiya	本宮市	5233	3	0.06%	57
19	Koriyama	郡山市	53962	23	0.04%	43
20	Shirakawa	白河市	10805	6	0.06%	56
21	Miharu	三春町	2717	1	0.04%	37
22	Otama	大玉村	1372	2	0.15%	146
23	Ten-ei	天栄村	878	0	0.00%	0
24	Nishigo	西郷村	3618	1	0.03%	28
25	Izumizaki	泉崎村	1156	1	0.09%	87
	Subtotal	計	88587	42	0.05%	47.4
26	Soma	相馬市	5046	0	0.00%	0
27	Shinchi	新地町	1105	0	0.00%	0
	Subtotal	計	6151	0	0.00%	0
28	Iwaki	いわき市	47759	19	0.04%	40
	Subtotal	計	47759	19	0.04%	39.8
29	Sukagawa	須賀川市	11532	4	0.04%	35
30	Kagamiishi	鏡石町	1947	0	0.00%	0
31	Yabuki	矢吹町	2452	0	0.00%	0
32	Ishikawa	石川町	2078	1	0.05%	48
33	Yamatsuri	矢祭町	774	0	0.00%	0
34	Asakawa	浅川町	1067	0	0.00%	0
35	Tanagura	棚倉町	2256	1	0.04%	44
36	Hanawa	塙町	1210	0	0.00%	0
37	Ono	小野町	1317	0	0.00%	0
38	Furudono	古殿町	790	0	0.00%	0
39	Nakajima	中島村	801	0	0.00%	0
40	Hirata	平田村	824	1	0.12%	121
41	Samegawa	鮫川村	503	0	0.00%	0
42	Tamakawa	玉川村	984	0	0.00%	0
	Subtotal	計	28535	7	0.03%	24.5
43	Kitakata	喜多方市	5710	0	0.00%	0
44	Aizuwakamatsu	会津若松市	14632	5	0.03%	34
45	Minamiaizu	南会津町	1803	0	0.00%	0
46	Kaneyama	金山町	136	0	0.00%	0
47	Mishima	三島町	129	0	0.00%	0
48	Shimogo	下郷町	688	1	0.15%	145
49	Nishiaizu	西会津町	638	0	0.00%	0
50	Tadami	只見町	492	0	0.00%	0
51	Inawashiro	猪苗代町	1871	1	0.05%	53
52	Bandai	磐梯町	413	0	0.00%	0
53	Aizumisato	会津美里町	2547	0	0.00%	0
54	Aizubange	会津坂下町	2074	1	0.05%	48
55	Yanaizu	柳津町	375	0	0.00%	0
56	Hinoemata	檜枝岐村	61	0	0.00%	0
57	Showa	昭和村	101	0	0.00%	0
58	Kitashiobara	北塩原村	382	0	0.00%	0
59	Yugawa	湯川村	507	1	0.20%	197
	Subtotal	計	32559	9	0.03%	27.6

Tab 2: Incidence by municipality and March 15th plume

■ Incidence rate of each municipality and plume flow on March 15, 2011 analyzed by JAEA

Incidence rate per 100,000 (in red) in municipalities with more than 1,000 primary examination participants, superimposed on maps showing contaminated regions due to the March 15-16 radioactive plume, analyzed by JAEA

Sources: 

① Table 8 of "Thyroid Examination (Initial Screening) provisional results"

② "Formation of contaminated areas from the morning of March 15 to the afternoon of March 16" on page 16 of "Diffusion of Radioactive Iodine in the Environment: Based on the Model Calculation Results" by Masamichi Kayano, JAEA"

<Plume flow 1: March 15, 2011 from 6:00 am to 3:00 pm>

<Plume flow 2: March 15, 2011 from 3:00 pm to 9:00 pm>

<Plume flow 3: From 9:00 pm on March 15 to 6.00 am on March 16>

<Plume flow 1 to 3>

Tab 3: Incidence by municipality and soil contamination

■ Incidence rate of each municipality and soil contamination

Incidence rate per 100,000 (in red) in municipalities with more than 1,000 primary examination participants, superimposed on a map of radioactive cesium concentration in agricultural land

Source: The Ministry of Health, Labour and Welfare document, based on the radionuclide concentration distribution map in the agricultural land by the Ministry of Agriculture, Forestry and Fisheries (in Japanese)

Source: Elaboration of Iodine 131 Soil Concentration Map Through Determination of Iodine 129 (in Japanese)

19-Year-Old Fukushima Woman Says, "Please Let Me Be the One to Decide on My Own Life."

This is a translation of an interview article posted online on August 30, 2014, by a Japanese freelance journalist, Hiroki Suzuki. Suzuki runs a site called, "Tami no Koe Shimbun," or "People's Voice Newspaper," where he posts interviews of various people in Fukushima. The article was translated with permissions from Suzuki and the interviewee.


Tami no Koe Shimbun (People’s Voice Newspaper)
Let’s protect children from radiation exposure. Let’s protect people. That’s why I keep writing.

“Please let me be the one to decide on my own life.” A 19-year-old Date City woman talks about “nuclear accident,” “radiation exposure,” and “evacuation.”

I understand there is a danger of radiation exposure. I learned about dangers of nuclear power plant. But I don’t want to destroy my current life.... A 19-year-old college preparatory school student from Date City, Fukushima Prefecture, talked about how she really felt now that a little over three years have passed since the Tokyo Electric Fukushima Daiichi nuclear power accident. Her thyroid examination result showed “A2.” Meanwhile, there is a sense of security, “It might be okay.” from the fact that it has been three years. Saying “I want to make a decision on my life myself,” she continues to live in Date City while taking steps towards her dream of becoming a space engineer.

【Afraid of “Earthquake, Tsunami, and Nuclear Power】

March 11, 2011. It was the day of her graduation from junior high school. 

After coming home, she was relaxing on the second floor of her house when severe shaking began. All she could do was protect her own body under the table. She managed to close the curtains for fear of window glass breaking, but there was nothing else she was able to do. A tea cup fell and hit her on the buttock. When she collected her senses, she saw the room was in total destruction. 

As the aftershocks continued periodically, she went to pick up her younger brother with her father. Six years younger than her, he was in the third grade at the time. As he began to walk home with his father and sister, he started to cry. He was so scared when the earthquake happened. He was so afraid that he wanted to cry. But he held back his tears as he tried to cheer up his classmates so they wouldn’t cry.

There was no space in her house where they could lie down. It was the middle of winter in Fukushima. Snow began falling. It was bone cold. They ended up spending two nights in an unused vinyl green house. Lifeline such as electricity and water remained severed. Her worried mother sent the children to her parents’ house in Iisaka Town, Fukushima City. When she managed to have the cell phone fully charged, it showed multiple dubious chain e-mails. She said, “We couldn’t watch TV at all. Radio was only turned on occasionally. We had no idea there were serious events happening in Hamadori, let alone the nuclear power plant exploded…”

She came to realize there was something happening when she was playing soccer with her younger brother. Her aunt said, “There is something seriously wrong with the nuclear power plant.”

“It is often said, ‘Earthquake, thunder, fire, and father.’ I thought about which one is really the most frightening. You can prevent damages from thunder and fire. My father is scary when he is angry (laugh), but earthquake and tsunami, and nuclear power, are the most frightening.” 

The “frightening” incident actually happened. Soon, radiation levels within Date City exceed 20 μSv/h.


【Doubts About “Safety Promotion” at an Early Age】

She has been interested in nuclear power plants since in grade school. School textbooks only showed merits of nuclear power plants, but she says, “I was lucky to have a teacher who also taught us risks of nuclear power plants.” At the time, there were always events held in Fukushima City during summer breaks for “safety promotion.” She went to them every summer, but she never totally believed them. In the ninth grade, one of the summer homework assignments was to collect and summarize newspaper articles. You choose a theme, collect related articles, and summarize them. She chose “pluthermal, or plutonium-thermal use” as her theme. Recycling of uranium and plutonium collected during the reprocessing of spent nuclear fuel. She even read a book about it, and the more she dug into it, the more doubtful she became. She said “Only safety was emphasized. Why are they doing ‘safety promotion’?”

Therefore, it was natural that she began to seal all windows when returning home, in an attempt to protect her family from radiation, to the point where her father said, “Is all that really necessary?” She was pre admitted to high school during the first semester, so she didn’t have to go to the prefectural high school entrance examination result announcement which was held despite high radiation levels. However, she had to go and register for high school entrance, which meant she had to physically go to the prefectural high school she was admitted into. She covered herself with a mask and a muffler, minimizing skin exposure, and she washed her face carefully upon returning home. Even with all the precaution taken, the result of her thyroid ultrasound examination, done in January 2012, nine months after the high school began, was “A2” (nodules equal to or smaller than 5 mm or cysts equal to or smaller than 20 mm).

“I am worried if my future children will be affected when I get married and have babies.”

However, even three-plus years after the accident, she still hasn’t evacuated out of Fukushima Prefecture. Even when she might be admitted to a university, she is thinking about commuting from home. Why? She had conflicts which appeared to be shared with many other Fukushima residents. 

　
【I Want To Be the One to Decide on My Own Life】

“As radiation is colorless and invisible, I may not be connecting it with risk to my body… Also, although the air dose level in Date City was as high as 20 μSv/h immediately after the accident, I haven’t had any health effects. That makes me think maybe I will be okay.”

In the last 3 years, her parents tried various means of avoiding radiation exposure to protect her. She knows it will be difficult to evacuate out of Fukushima Prefecture for a financial reason and also because of caring for her ill grandparent. As her parents have tried hard, she thinks her family might be more protected than the others. She also feels anxious and lonely about living alone. 

She thought about it for a bit, and announced, “I was accepted into a particular high school I wanted to get into, in order to be closer to what I want to do in the future. I am afraid of destroying what I have by evacuating. Also, it’s my own life. I should be the one to decide.”

Her dream is to become a space engineer. She says with a smile, “I want to develop an engine for a space probe.” Two years ago she participated in a overnight learning camp at the Japan Aerospace Exploration Agency. She heard stories from an astronaut, Naoko Yamazaki. In order to fulfill her dream, she is studying to get into Tohoku University School of Engineering. “But I haven’t given up my other dream of becoming a dancer. I want to do both.” This year, she didn’t do well on the college entrance examination due to an illness. She commutes to a college preparatory school in Sendai, aiming to gain acceptance into Tohoku University next spring. 

“What people think about radiation exposure and evacuation isn’t black and white. It might be gray close to being white, or gray close to being black. Perhaps another color would blend in. Many people think of radiation the same as air, but some people are working very hard to reduce the risk. I would like people outside Fukushima Prefecture to understand that.”

Two and a half year since the last examination, she had a repeat thyroid ultrasound examination at Fukushima Medical University. After the ultrasound examination, she said, “I saw cysts on the monitor.”

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)