While thyroid nodules are less common in children than in adults, they are more frequently malignant. However, pediatric data are scarce regarding the performance characteristics of imaging and cytopathology classification systems validated to predict the risk of malignancy (ROM) in adults and select those patients who require fine-needle aspiration (FNA) and possibly surgical resection. We retrospectively reviewed the electronic medical records of all patients 18 years of age or younger who underwent thyroid FNA at our institution from 1 July 2015 to 31 May 2022. Based on surgical follow-up from 74 of the 208 FNA cases, we determined the ROM for the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) ultrasound risk stratification system and The Bethesda System for Reporting Thyroid Cytopathology and added our results to those of pediatric cohorts from other institutions already published in the literature. We found the following ROMs for 1458 cases using ACR TI-RADS (TR): TR1. Benign: 2.2%, TR2. Not Suspicious: 9.3%, TR3. Mildly Suspicious: 16.6%, TR4. Moderately Suspicious: 27.0%, and TR5. Highly Suspicious 76.5%; and for 5911 cases using the Bethesda system: Bethesda I. Unsatisfactory: 16.8%, Bethesda II. Benign: 7.2%, Bethesda III: Atypia of Undetermined Significance: 29.6%, Bethesda IV. Follicular Neoplasm: 42.3%, Bethesda V. Suspicious for Malignancy: 90.8%, and Bethesda VI. Malignant: 98.8%. We conclude that ACR TI-RADS levels imply higher ROMs for the pediatric population than the corresponding suggested ROMs for adults, and, in order to avoid missing malignancies, we should consider modifying or altogether abandoning size cutoffs for recommending FNA in children and adolescents whose thyroid glands are smaller than those of adults. The Bethesda categories also imply higher ROMs for pediatric patients compared to adults.
尽管甲状腺结节在儿童中的发生率低于成人，但其恶性比例更高。然而，针对已成人验证用于预测恶性风险（ROM）并筛选需行细针穿刺活检（FNA）及可能手术切除患者的影像学与细胞病理学分类系统，在儿童群体中的性能特征数据仍十分有限。我们回顾性分析了2015年7月1日至2022年5月31日期间在本机构接受甲状腺FNA的所有18岁及以下患者的电子病历。基于208例FNA中74例的手术随访结果，我们计算了美国放射学会甲状腺影像报告与数据系统（ACR TI-RADS）超声风险分层系统和甲状腺细胞病理学Bethesda报告系统的ROM，并将结果与已发表文献中其他机构的儿童队列数据合并分析。通过对1458例ACR TI-RADS（TR）病例的分析，我们发现各分级恶性风险分别为：TR1良性2.2%、TR2无可疑特征9.3%、TR3轻度可疑16.6%、TR4中度可疑27.0%、TR5高度可疑76.5%；对5911例Bethesda系统病例的分析显示：I类不满意标本16.8%、II类良性7.2%、III类意义不明的非典型病变29.6%、IV类滤泡性肿瘤42.3%、V类可疑恶性90.8%、VI类恶性98.8%。我们得出结论：ACR TI-RADS分级在儿童群体中提示的恶性风险高于成人参考标准，且为避免漏诊恶性肿瘤，应考虑修改或完全取消基于结节大小推荐FNA的阈值，因为儿童甲状腺体积普遍小于成人。Bethesda分类系统在儿童患者中也显示出比成人更高的恶性风险。
肿瘤(癌症)患者之家