ORLANDO, Fla. — The overall incidence of thyroid cancer is “leveling off” in the United States, but rising among young, black and Hispanic populations, researchers reported at the Endocrine Society Annual Meeting.
To examine recent trends in thyroid cancer in different age, race and sex subgroups, Anupam Kotwal, MBBS, clinical fellow at the Mayo Clinic, Rochester, Minnesota, Juan P. Brito, MBBS, assistant professor of medicine at Mayo Clinic, and colleagues reviewed rates from the National Cancer Institute Surveillance, Epidemiology and End Results (SEER 18) program from 2000 to 2013.
Juan P. Brito
During that period, the incidence of thyroid cancer rose from 7.4 cases per 100,000 people to 14.5 cases per 100,000 people. The average percent change increase was 6.7% from 2000 to 2009 and 2.4% from 2010 to 2013 (P < .05 for both).
When the researchers analyzed trends among specific racial groups, they found that the incidence of thyroid cancer has continuously increased, with an annual percent change increase of 4.7% in the black population and 5.1% in the Hispanic population. In contrast, there was a deceleration in thyroid cancer incidence among non-Hispanic whites, from 7.1% before 2009 to 2.2% after 2009, according to results presented.
Analysis by age revealed continued acceleration at an unchanged rate only among people aged 20 years and younger. In the older age groups, the rising incidence of thyroid cancer stabilized after 2009 in those aged 75 years and older, with an average 1% change, Kotwal said during a press conference.
Both women and men showed similar deceleration in overall rates of thyroid cancer after 2009. The annual percent change was 2.3% among women and 2.8% among men, according to results presented.
When the researchers combined subgroups based on their association with acceleration or deceleration rates, Hispanic women aged 20 to 49 years had the highest average percent change, with no evidence of deceleration, Kotwal said.
“These findings are consistent with recent reports demonstrating that thyroid cancer is the second most common cancer among Hispanic females, female adolescents and young adults,” the researchers concluded.
According to Kotwal, it is unclear whether the rising incidence is some groups is greater due to more testing or whether there has been a true change in the incidence of thyroid cancer.
“Drivers for these disparities need to be further evaluated,” he said.
Nevertheless, the findings of the current study are important because they suggest “age, sex and racial disparities in [the incidence of thyroid cancer], with possible implications in disease-specific outcomes as well as societal and economic costs,” Kotwal said. – by Katie Kalvaitis
Kotwal A, et al. SH04-6. Presented at: The Endocrine Society Annual Meeting; April 1-4, 2017; Orlando, Fla.
Disclosures: One researcher reports consulting and speaking for Sigma-Tau Pharmaceuticals. The other researchers report no relevant financial disclosures.