Section of Endocrinology, Department of Biomedical Sciences and Advanced Therapies, University of Ferrara, Via Savonarola 9, 44121 Ferrara, Italy.
J Clin Endocrinol Metab. 2012 Jul;97(7):2354-61. doi: 10.1210/jc.2011-3494. Epub 2012 Apr 24.
Ultrasound (US)-guided fine-needle aspiration biopsy (FNAB) is the most reliable nonsurgical test for distinguishing benign from malignant thyroid nodules. However, there is no consensus on which nodules should undergo FNAB.
The aims of this study were to evaluate the utility of US-guided FNAB in the diagnostic assessment of nodules with or without clinical/US features suggestive for malignancy and to investigate the additional contribution of BRAF V600E mutation analysis in the detection of differentiated thyroid cancer.
Thyroid cytoaspirates from 2421 nodules at least 4 mm in diameter were performed in 1856 patients who underwent cytological evaluation and biomolecular analysis.
Cytology showed high positive predictive value and specificity for the diagnosis of malignant lesions. BRAF V600E mutation was found in 115 samples, 80 of which were also cytologically diagnosed as papillary thyroid cancer. BRAF mutation analysis significantly enhanced the diagnostic value of cytology, increasing FNAB diagnostic sensitivity for malignant nodules by approximately 28%. Micro PTC (63% of diagnosed papillary thyroid carcinoma) showed a high prevalence of multifocality, extrathyroidal extension, and lymph node metastases, underlining the malignant potential of thyroid microcarcinomas. Each investigated US/clinical characteristic of suspected malignancy correlated with the presence of a thyroid cancer in thyroid nodules with diameter of at least 4 mm.
These data indicate that nodules of at least 4 mm may underlie a thyroid cancer independently of US/clinical characteristics of suspected malignancy, suggesting the need to perform FNAB. The diagnostic sensitivity for thyroid cancer is significantly increased by BRAF V600E mutation analysis, indicating that the screening for BRAF mutation in FNAB samples has a relevant diagnostic potential.
超声（US）引导下细针穿刺活检（FNAB）是区分甲状腺良恶性结节最可靠的非手术检查方法。然而，对于哪些结节应该进行 FNAB，尚无共识。
本研究旨在评估超声引导下 FNAB 在具有或不具有提示恶性的临床/US 特征的结节的诊断评估中的作用，并探讨 BRAF V600E 突变分析在检测分化型甲状腺癌中的额外贡献。
对 1856 例至少 4 毫米直径的甲状腺结节进行了甲状腺细针抽吸细胞学检查和生物分子分析。
细胞学检查对恶性病变的诊断具有较高的阳性预测值和特异性。在 115 个样本中发现了 BRAF V600E 突变，其中 80 个样本在细胞学上也被诊断为甲状腺乳头状癌。BRAF 突变分析显著提高了细胞学的诊断价值，使恶性结节的 FNAB 诊断敏感性提高了约 28%。微小甲状腺癌（诊断为甲状腺乳头状癌的 63%）多发病灶、甲状腺外侵犯和淋巴结转移的发生率较高，强调了甲状腺微小癌的恶性潜能。每个可疑恶性的 US/临床特征与至少 4 毫米直径的甲状腺结节中存在甲状腺癌相关。
这些数据表明，至少 4 毫米的结节可能独立于 US/临床可疑恶性特征而存在甲状腺癌，提示需要进行 FNAB。BRAF V600E 突变分析显著提高了甲状腺癌的诊断敏感性，表明 FNAB 样本中 BRAF 突变的筛查具有相关的诊断潜力。
