Thyroid Cancer Research Unit
Osaka University Graduate School of Medicine

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 Revolution in Cancer Research Starting from Thyroid
 Our group first reported the data on gene expression profiles in thyroid tumors and proposed a novel theory of thyroid carcinogenesis, fetal cell carcinogenesis, in 2000. Fetal cell carcinogenesis is now regarded as a major theory to explain the overdiagnosis of juvenile thyroid cancer. We establised Aspiration Biopsy Nucleic Acid Diagnosis (ABND) using TFF3-based analysis and FACS-mQ with which stem cells or cancer-initiating cells are analyzed efficiently and quickly.

Fetal Cell Carcinogenesis
Thyroid tumors are derived directly from fetal thyroid cells

Recent evidences that support fetal cell carcinogenesis

PDKorean's thyroid cancer "Epidemic"

 Preventive surgical resection of papillary thyroid microcarcinomas (PTMs) did not decrease cancer-related mortality, which suggested that PTMs do not progress to lethal cancers.

QDFukushima Health Management Survey

 1/2700 children were diagnosed with thyroid cancer, which suggested that the prevalence of juvenile thyroid cancer is high even in children.

RDObservation trials of PTM

 1) PMCs grow very slowly after middle age. 2 ) PMCs in younger patients grow faster. 3) No patient died from thyroid cancer during the trails. These data suggested that thyroid cancer initiates before adolescence, grows fast in teens and twenties, but does not progress to lethal one.

 SDWhole exome sequencing using samples in which both differentiated and anaplastic thyroid carcinomas co-exist

 Two carcinomas shared only a limited number of genetic alternation. There were many genetic alternations found only in gdifferentiatedh carcinomas. These results suggested these two may share a common origin, but developed independently.

For more information and free PDF

ZNatural history of thyroid cancers. Endocr J 64:237-244, 2017

Overdiagnosis of Juvenile Thyroid Cancer
Early diagnosis of self-limiting cancner results in overdiagnosis

The fetal cell carcinogenesis theory suggested the existence of self-limiting cancer, which acts as cancer by causing invasion and metastasis, but shows limited ability of proliferation—early diagnosis of such cancer results in overdiagnosis. Recent clinical data showed that juvenile thyroid cancer acts like self-limiting cancer. As a member of the Oversight Committee of the Fukushima Management Survey and the Task Force for Thyroid Examination in Fukushima, Japan (2017-2019), Dr. Takano warned of the harm of thyroid US screening for children which is now ongoing in Fukushima.

Three actions to be undertaken to prevent overdiagnosis of juvenile thyroid cancer (by Takano T, 2017)

1. Experts should publicize their honest opinion without a misleading caused by conflicts of interest.

2. Residents should educate themselves to avoid the epidemic of fear and popularity paradox.

3. All the related should give priority to protect children from the harm of overdiagnosis over their own interests.

For more information and free PDF

1. Takano T. Overdiagnosis of thyroid cancer in Fukushima. J Soc Risk Analysis, Japan 28:67-76, 2019 (In Japanese, abstract in English)@Free PDF

2. Takano T. Overdiagnosis of thyroid cancer: The children in Fukushima are in a danger. Arch Pathol Lab Med 143:660-661, 2019 Open Access

3. Takano T. Overdiagnosis of juvenile thyroid cancer (review) Eur Thyroid J 9:124-131, 2020 Open Access

4. Takano T. Overdiagnosis of juvenile thyroid cancer: Time to consider self-limiting cancer. (perspective) J Adolescent Young Adult Oncol 9: 286-288, 2020  Open Access

5. Takano T. In reply: An accurate picture of Fukushima's thyoid ultrasound examination program. Arch Pathol lab Med 144: 797-798, 2020 Open Access



Toru Takano MD Associate Professor
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[Past presentations in international conferences]
1) Toru Takano: Preoperative molecular diagnosis of thyroid nodule: How does it help? (Lecture)
The 3rd Asian Masterclass of Thyroid Cancer, Taipei, Taiwan, 2014
2) Toru Takano: Fetal cell carcinogenesis: present status and future prospect (Symposium)
The 21st International Symposium on Molecular Thyroidology, Osaka Japan, 2014
3) Toru Takano: Molecular-based classification of thyroid tumor for the use of pre-and post operative diagnoses (Lecture)
The 4th Asian master class of Thyroid Cancer, Hong Kong, China, 2015
4) Toru Takano: Fetal cell carcinogenesis of the thyroid (Symposium)
2015Annual Autumn Meeting of Korean Endocrine Society, Busan, Korea, 2015