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

ABSTRACT

PURPOSE: To investigate the association between age distribution and synchronous distant metastasis of papillary thyroid carcinoma. METHOD: 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. RESULTS: 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. CONCLUSIONS: A U-shaped association was observed between age at diagnosis and synchronous distant metastasis in papillary thyroid carcinoma patients.