[Correlations of serum TgAb and TPOAb and clinicopathological features of PTC in children and adolescents]

Abstract

Objective: To analyze the correlations between serum thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb) and clinicopathological features in children and adolescents with papillary thyroid carcinoma (PTC). Methods: A retrospective analysis was conduced on the clinicopathological data of children and adolescents (age≤21 years old) with PTC admitted to Tianjin Medical University Cancer Hospital from 2011 to 2019, and then, we used χ² test or Fisher's exact probability test to compare the differences in clinicopathological characteristics between groups with different TgAb and TPOAb status and multivariate logistic regression model analysis to evaluate independent predictors of cervical lymph node metastasis. Results: A total of 304 patients, including 89 males and 215 females, aged 5-21 years (median age 19 years), were enrolled in this study. The comparison between groups with different TgAb and TPOAb status showed that there were significant differences in gender, preoperative thyroglobulin (Tg) level, primary tumor location, number of primary tumors and maximum tumor diameter (all P<0.05), which suggested that TgAb⁺group (n=81) and TPOAb⁺group (n=84) had relatively better primary tumor characteristics. Patitents with TgAb⁺and TPOAb⁺were more common in females and their preoperative Tg level was mostly within the normal range, and there were significant differences in primary tumor location, number of primary tumors and maximum tumor diameter between TgAb⁺and TgAb^-(223 cases) groups (all P<0.05). There was significant difference in the maximum tumor diameter between TPOAb⁺and TPOAb^-(220 cases) groups (P<0.05). Analysis of risk factors for cervical lymph node metastasis showed that independent risk factors for central lymph node metastasis were maximum tumor diameter>2 cm (OR=2.84, 95%CI: 1.59-5.07, P<0.001) and extra-thyroid extension (OR=0.32, 95%CI: 0.17-0.60, P<0.001), and independent risk factors for lateral neck lymph node metastasis included age≤14 years old (OR=0.34, 95%CI: 0.18-0.67, P=0.002), preoperative Tg⁺(OR=2.16, 95%CI: 1.10-4.24, P=0.026) and maximum tumor diameter>2 cm (OR=3.99, 95%CI: 2.33-6.82, P<0.001). Conclusion: It is recommended to test routinely serum TgAb and TPOAb before surgery in children and adolescents with PTC. Preoperative Tg⁺, age≤14 years, maximum tumor diameter>2 cm, and extra-thyroid extension are risk factors for cervical lymph node metastasis.