Relationship between recurrence and age in the diffuse sclerosing variant of papillary thyroid carcinoma: clinical significance in pediatric patients

Abstract

Abstract Purpose: The diffuse sclerosing variant (DSV) is an aggressive variant of papillary thyroid carcinoma (PTC), with higher prevalence in pediatric patients. However, due to its low incidence, few studies have assessed its characteristics. This study aimed to evaluate the relationship between recurrence and age in the diffuse sclerosing variant of papillary thyroid carcinoma. Methods: We retrospectively reviewed patients who were diagnosed with the DSV or conventional PTC (cPTC) after surgery at a medical center between May 1988 and January 2019. We compared the clinico-pathological characteristics and surgical outcomes of the DSV and cPTC groups, and between adult and pediatric patients with the DSV. Results: Among the 24,626 patient records reviewed, 202 were patients diagnosed with DSV and 24,424 were diagnosed with cPTC. Recurrence rate was significantly higher in the DSV group compared to the cPTC group. Additionally, in the DSV group, recurrence rate was significantly higher in pediatric patients compared to adult patients. Moreover, we observed that the association between recurrence and age group showed different patterns between DSV and cPTC patients with restricted cubic splines (RCS). While both RCS curves showed a U-shaped distribution, the RCS curve tended to locate within the pediatric group. Conclusion: This study demonstrated that pediatric patients with the DSV are at a greater risk for recurrence compared to adult patients, and show a different pattern of recurrence risk according to age from that of cPTC.