“Korea’s Thyroid-Cancer Screening and Incidence Rates” from the Research Team of Professor Hyeong Sik Ahn, Preventive Medicine Class of Korea University’s College of Medicine, is Published in NEJM, One of the World’s Most Prestigious Biomedical Science Journals
▲ Professor Hyeong Sik Ahn (left), Research Professor Hyun Jung Kim (right)
The research team of Professor Hyeong Sik Ahn, Preventive Medicine Class of Korea University’s College of Medicine, presented a paper entitled “Korea’s Thyroid-Cancer Screening and Incidence Rates”, which was published in one of the world’s most prestigious bio-medical science journals, the New England Journal of Medicine (NEJM).
* First Author (Dr. Hyeong Sik Ahn, Professor of Preventive Medicine Class & Director of Institute for Evidence-based Medicine), Second Author (Dr. Hyung Jung Kim, Research Professor of Institute for Evidence-based Medicine)
The research examines the relevancy between the past two years’ thyroid-cancer screening reported to the Community Health Survey 2012 and the regional incidence of thyroid cancer, and explains, for the first time, that the screening is the reason for the 15-times increased rate of thyroid cancer diagnoses in 2011, compared to that observed in 1993.
Especially, guidelines recommend observation without surgery for thyroid tumors less than 0.5 centimeter in diameter. According to domestic research data, the incidence of thyroid-cancer has not continuously increased. However, the proportion of patients undergoing surgery for thyroid tumors measuring less than one centimeter in diameter has increased from 14% in 1995 to 56% 10 years later. This causes the incensement of thyroid-cancer surgery for tumors of smaller size.
Treatment of thyroid cancer has substantial consequences for patients because it leads to lifelong thyroid hormone therapy and side effects.
Also, according to the Five Continents database, thyroid-cancer incidence has more than doubled in many countries other than Korea (the United States, Canada, the Czech Republic, France, Italy, Israel, and others) Thus, it is not just a domestic problem, but it can become a worldwide problem.
According to Prof. Ahn, “Because every type of cancer is regarded as fatal, there is no way to avoid medical treatment for both patients and doctors. Therefore, many subclinical thyroid tumors that won’t be developed are detected and treated by unnecessary screening.”
NEJM, which published the paper, is the world’s most prestigious biomedical science journal with a higher impact factor (impact factor: 54.4) than well-known science journals such as Cell (33.1), Science (31.4) and Nature (42.4); only about 10 Korean scientists have published papers in NEJM to date.
This research, as drawing worldwide attention, proves that an important social system (a national screening program) for maintaining optimal quality of medical care which is emphasized by the fields of preventive medicine and medical care can lead to serious social problems if it is not based on proper grounds. It is quite an exceptional result that NEJM, whose main research field is clinical research, approves these research results, and means that the field of clinical medicine approves controversy in the field of preventive medicine.
The following is a brief summary of the research.
The Republic of Korea has recently scored the world’s most dramatic increase in the incidence rate of thyroid cancer. The research team has analyzed different types of big data to find the causes of the increase. In the process, sorting out reliable research papers was significant. Big data in the screening and cancer registry (about a million people), in the Community Health Survey (about 200,000 people), and in the Statistics Korea (about 10,000 people) are used for integral analysis. As a result, the research team made the world’s first result of establishing the cause of thyroid-cancer incidence of Korea, which is the highest in the world. According to the research, it is closely related to a national screening program apart from biomedical factors of Koreans. The research team argues that a national screening program based on medical grounds should be instituted to secure the national health safety net because groundless cancer screening causes unnecessary fears in patients and cost inefficiency in medical expenses for the country.