Incidence and prognosis of thyroid cancer in children: based on the SEER database

To update the recognition of the trends in the incidence of childhood thyroid cancer (TC) and its prognosis.

A large-scale sample based on long time-line public database was recruited. Join-point regression model was used to analyze the incidence trend of childhood TC. Univariable and multivariable Cox regression model analyses were applied to explore the survival situation and prognostic factors.

The incidence rate of childhood TC increased between 1975 and 2016 from 3.8/million (95% CI 2.6-5.5) to 11.5/million (95% CI 9.2-14.1), AAPC = 2.38% (95% CI 1.98-9.65) and could be divided into two stages of increasing trends. The incidence rate of Trend1 (1975-2005) increased slowly (APC = 1.08%, 95% CI 0.38-1.82) while Trend2 (2005-2016) increased dramatically (APC = 6.77%, 95% CI 4.30-9.28). Annual incidence rate of small size tumor (< 4 cm) and local stage childhood TC increased significantly. The overall cumulative survival rate for childhood TC was high up to 97-99%. Males, black race, MTC type, distant metastasis, tumor size ≥ 4 cm, non-primary cancer were the independent risk factors of childhood TC prognosis.

A contribution of overdetection to rising pediatric TC rates might not be able to rule out. For clinical implications, screening TC in children with potential specific risk factors is feasible. Over-treatment to small size and local stage TC in children should be avoided.