Increasing Incidence of Papillary Thyroid Cancer Linked to Overdiagnosis
The rapid increase in papillary thyroid cancer in the United States may not be linked to increase in occurrence, but instead may be linked to an increase in the diagnosis of precancerous conditions and to a person's insurance status, according to a study published online in Thyroid.
"This [study] shows that access to health care is an important driver in the rising incidence of thyroid cancer," said senior author Louise Davies, MD, MS, Assistant Professor of Surgery at the Geisel School of Medicine, Dartmouth, in New Hampshire. "People with insurance are more likely to be diagnosed with thyroid cancer than those without insurance." In addition researchers found that higher education levels and higher rates of white collar employment were also associated with increased diagnosis rates.
Study Details
Researchers used the Surveillance, Epidemiology, and End Results database to examine papillary thyroid cancer incidence trends in Medicare-age and non–Medicare-age cohorts over 3 decades. They found that papillary thyroid cancer is increasing in incidence at a rate of 8.8% a year in Americans over age 65 who have health insurance coverage through Medicare. Among adults under age 65, who do not have access to Medicare, the rate of increase is 6.4%. The mortality rate from thyroid cancer, however, has not changed over 3 decades.
Incidence varied widely across the 497 U.S. counties analyzed, with thyroid cancer incidence significantly correlated with the sociodemographic markers of health-care access; more papillary thyroid cancers were diagnosed in populations with wider access to health care.
Next Steps
"We did the study to understand who is at risk of being diagnosed with thyroid cancer, which is now—like prostate cancer—recognized to be a disease that is commonly overdiagnosed," said Dr. Davies, adding, "The findings are counterintuitive for many: Having good health insurance puts you at risk for something bad—the unnecessary identification and treatment of a cancer that was never destined to cause a problem.”
According to Dr. Davies, "As a next step we should look to protect patients from unnecessary workups of thyroid findings that do not present a significant threat to their health."
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
