Nam Se Jin, Kwak Jin Young, Moon Hee Jung, Yoon Jung Hyun, Kim Eun-Kyung, Koo Ja Seung
Department of Radiology, Severance Hospital, Research Institute of Radiological Science, Yonsei University, College of Medicine, Seoul, Korea.
Department of Pathology, Severance Hospital, Yonsei University, College of Medicine, Seoul, Korea.
PLoS One. 2017 Oct 12;12(10):e0186242. doi: 10.1371/journal.pone.0186242. eCollection 2017.
There is controversy about the accuracy of the fine-needle aspiration (FNA) cytology results in large sized thyroid nodules. Our aim was to evaluate the false-negative rate of FNA for large thyroid nodules and the usefulness of the Thyroid Imaging Reporting and Data System (TIRADS) in predicting false-negative cytology for large thyroid nodules with benign cytology.
632 thyroid nodules larger than or equal to 3cm in size with subsequent benign cytology on US-guided FNA were included. US features of internal composition, echogenicity, margin, calcifications, and shape were evaluated, and nodules were classified according to TIRADS. TIRADS category 3 included nodules without any of the following suspicious features:solidity, hypoechogenicity or marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape. Category 4a, 4b, 4c, and 5 were assigned to nodules showing one, two, three or four, or five suspicious US features, respectively. US features associated with malignancy for these lesions were analyzed and malignancy risk according to TIRADS was calculated.
Of the 632 lesions, 23 lesions(3.6%) were malignant and 609(96.4%) were benign, suggesting a 3.6% false-negative rate for FNA cytology. Of the 23 malignant lesions, final pathology was mainly follicular carcinoma minimally invasive(65.2%, 15/23) and the follicular variant of papillary carcinoma(26.1%, 6/23). The malignancy risks of categories 3, 4a, 4b, and 4c nodules were 0.9%, 4.6%, 10.0%, and 11.8%, respectively.
Large thyroid nodules with benign cytology had a relatively high false-negative risk of 3.6% and TIRADS was helpful in predicting false-negative cytology for these lesions.
对于粗针穿刺（FNA）细胞学检查结果在大型甲状腺结节中的准确性存在争议。我们的目的是评估大型甲状腺结节FNA的假阴性率，以及甲状腺影像报告和数据系统（TIRADS）在预测大型甲状腺结节良性细胞学检查假阴性方面的实用性。
纳入632个大小大于或等于3cm且超声引导下FNA细胞学检查结果为良性的甲状腺结节。评估内部成分、回声、边界、钙化和形状的超声特征，并根据TIRADS对结节进行分类。TIRADS 3类包括没有以下任何可疑特征的结节：实性、低回声或显著低回声、微叶状或不规则边界、微钙化以及纵横比大于1。4a、4b、4c和5类分别分配给显示一个、两个、三个或四个或五个可疑超声特征的结节。分析这些病变与恶性相关的超声特征，并计算根据TIRADS的恶性风险。
在632个病变中，23个病变（3.6%）为恶性，609个（96.4%）为良性，提示FNA细胞学检查的假阴性率为3.6%。在23个恶性病变中，最终病理主要为微小浸润性滤泡癌（65.2%，15/23）和乳头状癌滤泡变体（26.1%，6/23）。3类、4a类、4b类和4c类结节的恶性风险分别为0.9%、4.6%、10.0%和11.8%。
细胞学检查为良性的大型甲状腺结节假阴性风险相对较高，为3.6%，TIRADS有助于预测这些病变的假阴性细胞学检查结果。
