Surge in Thyroid Cancer Cases May Be Due to This
Many might be getting unnecessary treatment for slow-growing disease, some experts say
Welch noted that the treatment of many cancers is changing.
"Medicine is in the midst of a course correction. We've believed for years that the best strategy for cancer was to find as much as we could, but we are realizing that the population harbors a lot of early cancer, and we have to make sure we don't create more problems than we solve by looking for them," he said.
For the study, Welch and his colleague, Dr. Louise Davies of the VA Medical Center in White River Junction, Vt., used federal government data to study patients diagnosed with thyroid cancer from 1975 to 2009.
The investigators found that since 1975, the incidence of thyroid cancer has almost tripled, from 4.9 to 14.3 cases per 100,000 people. Nearly all of this increase has been of papillary thyroid cancer -- from 3.4 to 12.5 per 100,000 people.
The biggest increase was seen among women -- from 6.5 to 21.4 cases per 100,000 women. That's nearly four times more than it is for men, which went from 3.1 to 6.9 cases per 100,000 men, the researchers noted.
Although the number of thyroid cancers diagnosed has increased dramatically, the death rate from the disease hasn't changed, remaining at about 0.5 deaths per 100,000 people, the researchers added.
Commenting on the study, Dr. Brian Burkey, an otolaryngologist at the Cleveland Clinic, said: "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."
Burkey said current treatment calls for a biopsy of thyroid nodules, which can lead to removing the thyroid. "There is really only one treatment for papillary thyroid cancer -- surgery," he said.
After the thyroid is removed, patients have to take medication to replace thyroxine and triiodothyronine, the hormones produced by the thyroid.
"The question is, 'Do we need to treat all these thyroid cancers?'" Burkey said. There is mounting evidence that watchful waiting might be a good alternative, but it's too early to start using this as a standard treatment. That will have to wait until there are clinical trials that prove this is a good option, he explained.
Cooper added, "Until we learn to accept small thyroid cancers as less worrisome than we now consider them to be and educate our patients about the non-lethal nature of the disease, the upward trend in thyroid cancer diagnosis and treatment will continue."