The New York Times published a great story about the tremendous growth of thyroid cancer diagnoses in South Korea. It’s based on a study authored by H. Gilbert Welch, MD, a professor at Dartmouth Medical School, who has been a voice of restraint in the growth of aggressive American medicine for 3 decades.
The study documents a 15-fold increase in the diagnoses in thyroid cancers since the country started a national screening program. But there has been no increase in the incidence of severe thyroid cancers or a decrease in thyroid cancer deaths.
This happened for the same reasons PSA testing for prostate cancers don’t work: 1) many people have thyroid cancer, but 2) most of the cases are very non-aggressive, which means 3) most people with thyroid cancer die with the disease not because of the disease.
This means thousands of Koreans have been needlessly scared and scarred by unnecessary tests. It also serves as a great reminder of one of the counter-truths of the POEM assumptions: early detection of a disease often does not change the ultimate outcome.