Abstract
The Fukushima nuclear power plant accident occurred on March 11, 2011, following the Great East Japan earthquake and tsunami. Radioactive materials, including 131I, were released into the environment after the accident. Therefore, the government initaiated the Fukushima Health Management Survey for monitoring long-term health condition of the residents in Fukushima Prefecture. In the survey, thyroid ultrasonography is scheduled for all the people under 18 years of age who were living in Fukushima Prefecture at the time of disaster. The total number of examinees is 360,000. First, thyroid ultrasonography is performed as a screening test. When abnormal findings are detected, thyroid FNAC is performed. By the end of December 2013, the cytological specimens of 75 examinees had been interpreted as Malignant or Suspicious for malignancy. Histological examination of surgically removed specimens from 33 patients revealed papillary carcinoma. At the present time, it is difficult to conclude whether these papillary carcinomas were radiation-induced or not.
