Abstract：
BACKGROUND: Differentiated thyroid carcinoma (DTC) is a rare oncological disease in the pediatric population, presenting with a more aggressive form. Stimulated thyroglobulin (sTg) and the 131-iodine whole-body scans (WBSs) are known adult markers related to the presence of distant metastasis. Little is known about their roles in the pediatric population.
OBJECTIVE: To evaluate sTg levels and diagnostic WBS (DxWBS) as predictors of distant metastasis after thyroidectomy and to correlate with the response to treatment at the end of follow-up in pediatric DTC.
METHODS: Patients under 19 years old diagnosed with DTC from 1980 to 2022 were retrospectively evaluated. sTg values and WBS were assessed after thyroidectomy and prior radioiodine treatment (RIT) and correlated with the possibility of finding distant metastasis and response to treatment at the end of follow-up.
RESULTS: In a total of 142 patients with a median age of 14.6 (4-18) years who were followed for 9.5 ± 7.2 years and classified according to the ATA risk of recurrence as low (28%), intermediate (16%), and high risk (56%), 127 patients had their sTg evaluated. A sTg value of 21.7 ng/dl yielded a sensitivity of 88% compared to 30% for DxWBS in predicting distant metastasis. Specificity was 60% and 100% respectively. 42% of patients obtained discordant results between DxWBS and RxWBS. In high-risk patients, sTg levels were particularly able to differentiate those who would have distant metastasis with better diagnostic accuracy than the WBSs.
CONCLUSIONS: The sTg level had better performance in detecting distant metastases in pediatric DTC than the DxWBS. DxWBS\'s low performance suggests that caution should be taken in interpreting their findings in terms of the underdiagnosis for metastatic disease, especially when the sTg level already suggests distant disease.
OBJECTIVE: To evaluate sTg levels and diagnostic WBS (DxWBS) as predictors of distant metastasis after thyroidectomy and to correlate with the response to treatment at the end of follow-up in pediatric DTC.
METHODS: Patients under 19 years old diagnosed with DTC from 1980 to 2022 were retrospectively evaluated. sTg values and WBS were assessed after thyroidectomy and prior radioiodine treatment (RIT) and correlated with the possibility of finding distant metastasis and response to treatment at the end of follow-up.
RESULTS: In a total of 142 patients with a median age of 14.6 (4-18) years who were followed for 9.5 ± 7.2 years and classified according to the ATA risk of recurrence as low (28%), intermediate (16%), and high risk (56%), 127 patients had their sTg evaluated. A sTg value of 21.7 ng/dl yielded a sensitivity of 88% compared to 30% for DxWBS in predicting distant metastasis. Specificity was 60% and 100% respectively. 42% of patients obtained discordant results between DxWBS and RxWBS. In high-risk patients, sTg levels were particularly able to differentiate those who would have distant metastasis with better diagnostic accuracy than the WBSs.
CONCLUSIONS: The sTg level had better performance in detecting distant metastases in pediatric DTC than the DxWBS. DxWBS\'s low performance suggests that caution should be taken in interpreting their findings in terms of the underdiagnosis for metastatic disease, especially when the sTg level already suggests distant disease.
摘要：
背景：分化型甲状腺癌（DTC）是儿科人群中的一种罕见肿瘤疾病，以更具侵略性的形式呈现。受激甲状腺球蛋白（sTg）和131碘全身扫描（WBS）是已知的与远处转移有关的成人标志物。人们对它们在儿科人群中的作用知之甚少。
目的：评估sTg水平和诊断性WBS（DxWBS）作为甲状腺切除术后远处转移的预测因子，并与小儿DTC随访结束时对治疗的反应相关。
方法：对1980年至2022年诊断为DTC的19岁以下患者进行回顾性评估。在甲状腺切除术和先前的放射性碘治疗（RIT）后评估sTg值和WBS，并与发现远处转移的可能性和随访结束时对治疗的反应相关。
结果：共142例患者，中位年龄14.6（4-18）岁，随访9.5±7.2年，根据ATA复发风险分类为低（28%），中间（16%），高风险（56%），对127名患者进行了sTg评估。21.7ng/dl的sTg值在预测远处转移方面产生88%的灵敏度,而DxWBS为30%。特异性分别为60%和100%。42%的患者在DxWBS和RxWBS之间获得不一致的结果。在高危患者中，sTg水平特别能够区分那些具有比WBS更好的诊断准确性的远处转移。
结论：sTg水平在检测小儿DTC远处转移方面的表现优于DxWBS。DxWBS的低性能表明，在解释他们的发现时应该谨慎，因为对转移性疾病的诊断不足。特别是当sTg水平已经表明远处的疾病。
目的：评估sTg水平和诊断性WBS（DxWBS）作为甲状腺切除术后远处转移的预测因子，并与小儿DTC随访结束时对治疗的反应相关。
方法：对1980年至2022年诊断为DTC的19岁以下患者进行回顾性评估。在甲状腺切除术和先前的放射性碘治疗（RIT）后评估sTg值和WBS，并与发现远处转移的可能性和随访结束时对治疗的反应相关。
结果：共142例患者，中位年龄14.6（4-18）岁，随访9.5±7.2年，根据ATA复发风险分类为低（28%），中间（16%），高风险（56%），对127名患者进行了sTg评估。21.7ng/dl的sTg值在预测远处转移方面产生88%的灵敏度,而DxWBS为30%。特异性分别为60%和100%。42%的患者在DxWBS和RxWBS之间获得不一致的结果。在高危患者中，sTg水平特别能够区分那些具有比WBS更好的诊断准确性的远处转移。
结论：sTg水平在检测小儿DTC远处转移方面的表现优于DxWBS。DxWBS的低性能表明，在解释他们的发现时应该谨慎，因为对转移性疾病的诊断不足。特别是当sTg水平已经表明远处的疾病。
