Nanomaterials and Nanotechnology Research Center (CINN), Spanish National Research Council (CSIC), El Entrego, Asturias, Spain.
Health Research Institute of the Principality of Asturias (ISPA), Oviedo, Asturias, Spain.
Eur J Endocrinol. 2022 Jul 19;187(3):335-347. doi: 10.1530/EJE-22-0012. Print 2022 Sep 1.
The minimally invasive fine-needle aspiration cytology (FNAC) is the current gold standard for the diagnosis of thyroid nodule malignancy. However, the correct discrimination of follicular neoplasia often requires more invasive diagnostic techniques. The lack of suitable immunohistochemical markers to distinguish between follicular thyroid carcinoma and other types of follicular-derived lesions complicates diagnosis, and despite most of these tumours being surgically resected, only a small number will test positive for malignancy. As such, the development of new orthogonal diagnostic approaches may improve the accuracy of diagnosing thyroid nodules.
This study includes a retrospective, multi-centre training cohort including 54 fresh-frozen follicular-patterned thyroid samples and two independent, multi-centre validation cohorts of 103 snap-frozen biopsies and 33 FNAC samples, respectively.
We performed a genome-wide genetic and epigenetic profiling of 54 fresh-frozen follicular-patterned thyroid samples using exome sequencing and the Illumina Human DNA Methylation EPIC platform. An extensive validation was performed using the bisulfite pyrosequencing technique.
Using a random forest approach, we developed a three-CpG marker-based diagnostic model that was subsequently validated using bisulfite pyrosequencing experiments. According to the validation cohort, this cost-effective method discriminates between benign and malignant nodules with a sensitivity and specificity of 97 and 88%, respectively (positive predictive value (PPV): 0.85, negative predictive value (NPV): 0.98).
Our classification system based on a minimal set of epigenetic biomarkers can complement the potential of the diagnostic techniques currently available and would prioritize a considerable number of surgical interventions that are often performed due to uncertain cytology.
In recent years, there has been a significant increase in the number of people diagnosed with thyroid nodules. The current challenge is their etiological diagnosis to discount malignancy without resorting to thyroidectomy. The method proposed here, based on DNA pyrosequencing assays, has high sensitivity (0.97) and specificity (0.88) for the identification of malignant thyroid nodules. This simple and cost-effective approach can complement expert pathologist evaluation to prioritize the classification of difficult-to-diagnose follicular-patterned thyroid lesions and track tumor evolution, including real-time monitoring of treatment efficacy, thereby stimulating adherence to health promotion programs.
微创细针抽吸细胞学（FNAC）是目前诊断甲状腺结节恶性肿瘤的金标准。然而，正确区分滤泡性肿瘤通常需要更具侵袭性的诊断技术。缺乏合适的免疫组织化学标志物来区分甲状腺滤泡癌和其他类型的滤泡来源病变，这使得诊断变得复杂，尽管这些肿瘤大多数都通过手术切除，但只有少数会检测出恶性。因此，开发新的正交诊断方法可能会提高诊断甲状腺结节的准确性。
本研究包括一个回顾性、多中心培训队列，该队列包含 54 例新鲜冷冻滤泡模式甲状腺样本，以及两个独立的、多中心验证队列，分别包含 103 例冷冻活检样本和 33 例 FNAC 样本。
我们使用外显子组测序和 Illumina Human DNA Methylation EPIC 平台对 54 例新鲜冷冻滤泡模式甲状腺样本进行全基因组遗传和表观遗传分析。我们使用亚硫酸氢盐焦磷酸测序技术进行了广泛的验证。
使用随机森林方法，我们开发了一个基于三个 CpG 标记的诊断模型，随后使用亚硫酸氢盐焦磷酸测序实验进行验证。根据验证队列的结果，这种具有成本效益的方法可以区分良性和恶性结节，其敏感性和特异性分别为 97%和 88%（阳性预测值（PPV）：0.85，阴性预测值（NPV）：0.98）。
我们基于一组最小的表观遗传生物标志物的分类系统可以补充当前可用诊断技术的潜力，并优先考虑由于细胞学不确定而经常进行的大量手术干预。
近年来，被诊断患有甲状腺结节的人数显著增加。目前的挑战是对其进行病因诊断，以避免因甲状腺切除术而导致的恶性肿瘤。这里提出的方法，基于 DNA 焦磷酸测序检测，对恶性甲状腺结节的识别具有高敏感性（0.97）和特异性（0.88）。这种简单且具有成本效益的方法可以补充专家病理学家的评估，以优先分类难以诊断的滤泡模式甲状腺病变，并跟踪肿瘤演变，包括实时监测治疗效果，从而促进对健康促进计划的依从性。
