Spike in Thyroid Cases Due to Overdiagnosis
Since 1975, the statistics revealed that the number of diagnosed thyroid cases has nearly tripled. With increasing numbers, people might start to worry about thyroid cancer. However, according to a new study, the spike in the number of thyroid cases is caused by overdiagnosis, which suggests that the disease is also being overtreated.
"The incidence of thyroid cancer is at epidemic proportions, but it doesn't look like an epidemic of disease, it looks like an epidemic of diagnosis," said lead researcher Dr. H. Gilbert Welch, a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice, reported by WebMD. "This means that a lot of people are having their thyroids removed for a cancer that was never going to bother them."
According to the researchers, the rate of thyroid cases has jumped from 4.9 cases per 100,000 people in 1975 to 14.3 cases per 100,000 people in 2009. The majority of these cases was papillary thyroid cancer, with the incidence rate from 3.4 to 12.5 cases per 100,00 people. Papillary thyroid cancer is the more common and less aggressive form of thyroid cancer. Welch believes that this type of cancer could be treated using the watch-and-wait approach, which is often used for prostate cancer.
"We have to be really cautious that we don't create more problems than we solve. We will be looking hard at the question of watchful waiting for small papillary thyroid cancers, and we are going to be asking hard questions about whether we should even be looking for them," Welch said.
The research team added that highest increase in incidence rates was in women. From 1975 to 2009, the rate jumped from 6.5 to 21.4 cases per 100,000 women. For men, the incidence rate only increase from 3.1 to 6.9 cases per 100,000 men. The researchers added that despite these increases, the overall death rate from thyroid cancer stayed at around 0.5 deaths per 100,000 people.
"We are seeing a lot more thyroid cancer, but not deaths. Most of these cancers have 95 percent cure rates. But perhaps in certain cancers we are treating it too aggressively," Dr. Brian Burkey, an otolaryngologist at the Cleveland Clinic, said according to Philly.
The study was published in the journal, JAMA Otolaryngology - Head and Neck Surgery.