Thyroid nodules are a very common finding in the general population. Fine-needle aspiration (FNA) has been recommended as the initial test for the evaluation of thyroid nodules. The trend on reporting as atypia of undetermined significance (AUS) has been significantly increased, but the malignant risk is still controversial among different studies. The aim of this study is to investigate the malignancy risk of thyroid nodules reported as Bethesda category III (AUS/FLUS) on initial FNA.

We reviewed 272 papillary thyroid cancer (PTC) patients with suspicious thyroid nodules who underwent fine-needle aspiration and received surgical treatment during 2019 to 2020.

One hundred ten (40.4%) patients were diagnosed with PTC. Multivariate analysis showed that microcalcification (p = 0.037, OR = 2.260, 95% CI: 1.051–4.860), shape (p = 0.003, OR = 4.367, 95% CI: 1.629–11.705), diameters (p = 0.002, OR = 0.278, 95% CI: 0.123–0.631), anti-thyroglobulin antibodies (TGAb) (p = 0.002, OR = 0.150, 95% CI: 0.046–0.494), anti-thyroid peroxidase antibody (A-TPO) (p = 0.009, OR = 4.784, 95% CI: 1.486–15.401), and nodule goiter (p < 0.001, OR = 0.100, 95% CI: 0.046–0.217) were independent malignant risk factors in patients with thyroid nodule classified as Bethesda category III.

In this study, malignant risk factors in patients with thyroid nodule classified as Bethesda category III were significantly associated with preoperative serum TGAb, A-TPO, microcalcification, irregular shape, and nodule diameters. Nodules with malignant factors should be carefully elevated; surgery may be the better option for those patients.

甲状腺结节是一般人群中非常常见的发现。细针穿刺 (FNA) 已被推荐作为评估甲状腺结节的初始测试。报告为意义不明的非典型性 (AUS) 的趋势已显着增加，但在不同的研究中，恶性风险仍存在争议。本研究的目的是调查初始 FNA 报告为 Bethesda III 类 (AUS/FLUS) 的甲状腺结节的恶性风险。

我们回顾了 272 名疑似甲状腺结节的 PTC 患者，这些患者在 2019 年至 2020 年期间接受了细针抽吸术并接受了手术治疗。

110 名 (40.4%) 患者被诊断出患有 PTC。多变量分析显示微钙化 (p = 0.037, OR = 2.260, 95% CI: 1.051–4.860)、形状 (p = 0.003, OR = 4.367, 95% CI: 1.629–11.705)、直径 (p = 2, OR = 0. 0.278, 95% CI: 0.123–0.631), 抗甲状腺球蛋白抗体 (TGAb) (p = 0.002, OR = 0.150, 95% CI: 0.046–0.494), 抗甲状腺过氧化物酶抗体 (A-TPO) (p = 0.00) , OR = 4.784, 95% CI: 1.486–15.401) 和结节性甲状腺肿（p < 0.001, OR = 0.100, 95% CI: 0.046–0.217）是 Bethesda III 类甲状腺结节患者的独立恶性危险因素。

本研究中，Bethesda III类甲状腺结节患者的恶性危险因素与术前血清TGAb、A-TPO、微钙化、不规则形状和结节直径显着相关。有恶性因素的结节应小心抬高；对于这些患者，手术可能是更好的选择。