Re: Thyroid cancer: zealous imaging has increased detection and treatment of low risk tumours
A much more severe case of overdiagnosis of thyroid cancer can be found in Korea, in which the age-adjusted incidence rate of thyroid cancer per 100,000 persons increased from 7.2 in 1999 to 61.9 in 2010.1 The average annual percentage increase during 1999-2010 was 24.5% (23.7% in men and 25.7% in women). A total of 36, 021 cases of thyroid cancer was detected in 2010 alone in Korea, comprising 17.8% of all cancers.1 Thyroid cancer has become since 2009 the most common cancer in Korea. Despite the soaring incidence, clinicopathological characteristics and the mortality from thyroid cancer has been virtually unchanged in the same period.2
According to a cross-sectional survey conducted in 2009, a total of 13.2% of Korean adults (8.4% men and 16.4% women) underwent thyroid ultrasonography screening.3 The opportunistic general cancer screening program facilitated by both public warning and commercialized healthcare system with especially low public share expenditure on health seems to be a main contributor to this unprecedented increase of thyroid cancer in Korea.4
We speculate that overuse of thyroid ultrasonography screening in the general public would lead to similar increase of thyroid cancer incidence in other parts of world.
1. http://ncc.re.kr/english/infor/kccr.jsp. Korea Cancer Registry : Annual report of cancer statistics in Korea in 2010. 2012.
2. Cho BY, Choi H, Park YJ, et al. Changes in the clinicopathological characteristics and outcomes of thyroid cancer in Korea over the past 4 decades. Thyroid : official journal of the American Thyroid Association 2013.
3. Han MA, Choi KS, Lee HY, Kim Y, Jun JK, Park EC. Current status of thyroid cancer screening in Korea: results from a nationwide interview survey. Asian Pacific journal of cancer prevention : APJCP 2011;12:1657-63.
4. Lee TJ, Kim S, Cho HJ, Lee JH. The incidence of thyroid cancer is affected by the characteristics of a healthcare system. Journal of Korean medical science 2012;27:1491-8.
Competing interests: No competing interests