Risk factors for recurrence of differentiated thyroid carcinoma in children and adolescents: A retrospective cohort study

This study aimed to provide a recent clinical evaluation of the outcome of treatment and the predictors of recurrence for Chinese children and adolescents with differentiated thyroid carcinoma (DTC). This is a retrospective cohort study at the Yunnan Cancer Hospital from May 2002 to August 2021. We analyzed several risk factors related to the recurrence of DTC in children and adolescents. The Chi-square test, Kaplan–Meier log-rank tests, and Cox regression analysis were used in the statistical analysis. A P -value <.05 was considered statistically significant. A total of 103 patients were enrolled, including 68 girls (66.0%) and 35 boys (34.0%) with a median age of 18 years (range: 7–20 years). All enrolled patients received standard treatment. Children (≤14years) tended to have multifocality and higher levels of thyroid imaging reporting and data system, higher pN stage, and higher American Thyroid Association (ATA) pediatric risk compared with adolescents ( P < .05). The chief complaints and clinical treatment differed between children and adolescents. During a follow-up of 6 to 239 months (average 74.7 months, median 59 months), all patients survived, but recurrence occurred in 22 patients (22.4%). The disease-free survival rates at 1, 2, 5, and 10 years were 91.2%, 78.4%, 77.1%, and 77.1%, respectively. Univariate Cox regression and log-rank tests showed that positive preoperative thyroglobulin level, bilaterality, extrathyroidal extension, high pT/pN/pM stage, and high ATA pediatric risk were the risk factors for DTC recurrence in children and adolescents. Multivariate Cox regression found that extrathyroidal extension and ATA pediatric risk were independent risk factors for the recurrence of DTC in children and adolescents. Additionally, among the 38 cases with cN0 stage, one who had bilateral, and multifocal thyroid nodules experienced recurrence, while the remaining 37 cases with cN0 stage had no recurrence. In conclusion, compared with adolescents, children present with more highly malignant disease and are more prone to metastasis. The significant risk factors associated with the recurrence of DTC in children and adolescents were positive preoperative thyroglobulin level, bilaterality, high pT/pN/pM stage, extrathyroidal extension, and high ATA pediatric risk, with the latter 2 being independent risk factors. The surgical approach for cN0 patients should be personalized taking into account invasive features.