The U-Shaped association between age and distant metastasis in patients with papillary thyroid carcinoma

To investigate the association between age distribution and synchronous distant metastasis of papillary thyroid carcinoma.

Patients with PTC who were treated from January 2013 to December 2018 at a single institute in a cancer referral center in China were retrospectively reviewed. A logistic regression model with restricted cubic splines (RCS) was used to examine the association between age at diagnosis and synchronous distant metastasis.

A total of 111 patients (0.7%) were diagnosed with distant metastasis. The logistic regression model with RCS revealed a “U-shape” association between age and distant metastasis. The RCS curve suggested a U-shaped pattern. The multivariable regression analysis showed that patients in the age groups ≤21 years (OR 2.33, 95% CI 1.09–4.68, P = 0.022) and >55 years (OR 3.32, 95% CI 1.99–5.46, P < 0.001) had a significantly higher incidence of distant metastasis than patients in the age group of 22 to 55 years.

A U-shaped association was observed between age at diagnosis and synchronous distant metastasis in papillary thyroid carcinoma patients.