The number of young people in Fukushima Prefecture who have been diagnosed with definitive or suspected thyroid gland cancer, which is often associated with radiation exposure, has risen to 75, prefectural officials said Feb. 7.
The number of young people in Fukushima Prefecture who have been diagnosed with definitive or suspected thyroid gland cancer, which is often associated with radiation exposure, has risen to 75, prefectural officials said Feb. 7.
That is 16 more than in November, when figures were last released. The number of definitive cases rose by seven, from 26.
The 75 are among 254,000 individuals for whom results of thyroid gland tests have been made available to date.
Only residents of Fukushima Prefecture who were aged 18 or under at the time of the 2011 Fukushima nuclear disaster are eligible to receive the thyroid gland tests administered by the prefectural government.
The latest figures include the results from 28,000 more individuals compared to the numbers released in November.
Medical and government officials in Fukushima say they do not believe the cases of thyroid gland cancer diagnosed or suspected in the 75 young people in the prefecture are linked to the 2011 nuclear accident.
Hokuto Hoshi, who chairs a panel that discusses matters related to the prefectural survey on the health impact from radiation on Fukushima’s residents, referred to the fact that cases of thyroid gland cancer in children who lived near Chernobyl only began to increase four to five years after the 1986 nuclear accident.
Doctors at Fukushima Medical University said they will start analyzing genes in cancerous thyroid glands surgically removed from children to try to ascertain if radiation played a role in the pathology of their cancer.
"We hope to look for unknown types of gene mutations, other than those known to be associated with the generation of thyroid gland cancer, to study if they could serve as markers for determining if the cancers were induced by radiation," said Shinichi Suzuki, a professor of thyroid gland surgery with the university.
Even if exposure to radiation does increase the occurrence of thyroid gland cancer, it will take years before such a relationship can be established, whereas no method is currently available to determine whether individual cases of thyroid gland cancer were induced by radiation, Suzuki added.
The 75 young individuals with confirmed or suspected thyroid gland cancer, including one who was later diagnosed with a benign tumor, averaged 14.7 years in age when the Great East Japan Earthquake and tsunami triggered the meltdowns at the Fukushima No. 1 nuclear power plant in March 2011.
(This article was written by Teruhiko Nose and Yuri Oiwa.)