Introduction

Message from Professor Takashi Kudo,Professor
Department of Radioisotope Medicine,
Atomic Bomb Disease Institute, Nagasaki University
Professor Takashi Kudo

We rebooted our department as a department for clinical study of diagnostic/therapeutic use of radioisotope and basic research of radiation biology in 2010.
Ionizing radiation has two faces in medical field. One is the negative face such as oncogenesis. Another is the positive face which represented by diagnostic imaging and radiotherapy.
My specialty is a medical specialty called "nuclear medicine".
In nuclear medicine, very small amount of radioisotope is administered to the patient for diagnostic/therapeutic purpose. For example, diagnosis of ischemic heart disease such as angina pectoris which occurred with decreased blood supply to myocardium is properly diagnosed with radioisotope. The diagnosis of dementia such as Alzheimer’s disease and cerebrovascular disease is performed perfusion/metabolism imaging using radioisotope also. The diagnosis of neoplastic disease using FDG PET is also very famous. Not only diagnosis but the medical treatment using radioisotope such as I-131 and Y-90 is included in nuclear medicine. We are studying these issues.
Most of people have negative impression on the word "Radiation". However, it undoubtfully plays an essential role in recent advanced medical practices. For example, I-131, which is infamous related to the nuclear plant accident and the thyroid cancer risk, is very useful cure for the differentiated thyroid cancer metastasis nearly considered as "silver bullet". In the diagnostic field, FDG-PET which injects radioactive tracer called fluorodeoxyglucose becomes irreplaceable diagnostic tool for oncologic diagnosis. Not only for oncology, but also for neurology and cardiology, nuclear medicine plays important role for diagnosing such as dementia and cardiovascular diseases.
On the other hand, it is true that these medical examination is one of major cause of radiation burden of public. For example, in United states, major part of public radiation burden is related to medical practices, and roughly 10% of that is result of nuclear cardiology procedure performed for the diagnosis of ischemic heart diseases. Thus, in the United States, there is a controversy whether the use of nuclear cardiology is over-use or not.
As mentioned above, ionizing radiation has two in devisable two faces.
Our department have studied negative face of radiation such as effect of radiation cells and gene. Additionally, we will start positive face of radiation such as medical usage. We will contribute to the proper usage of radiation/radioisotope in medical practices.