Trends in papillary thyroid carcinoma among U.S. Youth ages 10-19: A SEER database analysis

This study aimed to evaluate trends in pediatric papillary thyroid carcinoma from 1975 to 2021, and to propose potential drivers of the observed trends via stratification by demographic characteristics.

A retrospective analysis was conducted of thyroid carcinoma cases in the Surveillance, Epidemiology, and End Results database for pediatric patients aged 10-19 years. Joinpoint Regression was used to identify significant changes in trends, calculating annual percent change and confidence intervals, stratified by sex, age, race/ethnicity, household income, and rural-urban continuum levels, with a null hypothesis of no change in incidence over time (ɑ = 0.05). Incidence rates were age-adjusted to the 2020 U S. standard population and household income was inflation-adjusted to 2022 U S. dollars.

Among 2117 cases, 79.5 % were female and 76.3 % were aged 15-19. The Joinpoint regression model demonstrated that incidence per 100,000 among females aged 15-19 rose significantly from 2006 to 2012 (annual percent change = 9.61 %, p < 0.05) but declined significantly from 2012 to 2021 (annual percent change = -3.60 %, p < 0.05). Declines were observed across income levels and geographic regions, but racial disparities persisted, with non-Hispanic White females showing a decrease, while rates for Hispanic females continued to rise.

Papillary thyroid carcinoma incidence among females aged 15-18 has declined significantly since 2012, the opposite of prior trends. Continued monitoring and further research are needed to understand these trends, including whether the observed decline may reflect changes in diagnostic practices or risk factor exposures.