Letsas K P, Andrikoula M, Tsatsoulis A
Division of Endocrinology, Department of Medicine, University Hospital of Ioannina, Greece.
Minerva Endocrinol. 2006 Jun;31(2):179-82.
Fine needle aspiration biopsy (FNAB)-based cytology is an accurate preoperative diagnostic method for the evaluation of thyroid nodules. Despite its high specificity and sensitivity, the results are non-diagnostic in a significant number of cases, commonly due to inadequacy of the samples or the presence of undetermined cellular morphology. Overlap-ping cytologic features among follicular-derived lesions are the most common causes of cyto-histopathologic discordances. The management of thyroid nodules with a non-diagnostic FNAB remains controversial. The significant probability of malignancy imposes either the repeat of the procedure or direct surgery. Recent studies have demonstrated the important role of molecular-based techniques such as RT-PCR in the diagnosis of thyroid lesions. Follicular cells obtained from the remaining material within the needle can be used for RNA extraction and then for RT-PCR amplification of specific mRNAs that are expressed in benign or malignant thyroid nodules. Furthermore, FNAB-RT-PCR in combination with molecular scanning techniques or direct sequencing provides a valuable screening tool for mutations. The present review highlights the applications of FNAB-RT-PCR method in the identification of new diagnostic molecular markers. The parallel molecular and cytological analysis of FNABs may contribute to a more accurate diagnosis and, thus, to a more specific clinical management of thyroid nodules.
基于细针穿刺活检（FNAB）的细胞学检查是评估甲状腺结节的一种准确的术前诊断方法。尽管其具有较高的特异性和敏感性，但在大量病例中结果仍无法诊断，通常是由于样本不足或存在无法确定的细胞形态。滤泡源性病变之间的细胞学特征重叠是细胞组织病理学不一致的最常见原因。FNAB结果无法诊断的甲状腺结节的处理仍存在争议。恶性肿瘤的高概率意味着要么重复该操作，要么直接进行手术。最近的研究表明，基于分子的技术如逆转录聚合酶链反应（RT-PCR）在甲状腺病变诊断中具有重要作用。从针内剩余材料中获取的滤泡细胞可用于RNA提取，然后用于对在良性或恶性甲状腺结节中表达的特定mRNA进行RT-PCR扩增。此外，FNAB-RT-PCR与分子扫描技术或直接测序相结合，为突变提供了一种有价值的筛查工具。本综述重点介绍了FNAB-RT-PCR方法在鉴定新的诊断分子标志物方面的应用。对FNAB进行平行的分子和细胞学分析可能有助于更准确的诊断，从而有助于对甲状腺结节进行更具针对性的临床管理。
