Department of Pathology, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, China.
Forevergen Biosciences Center, Guangzhou, China.
J Clin Lab Anal. 2020 Nov;34(11):e23458. doi: 10.1002/jcla.23458. Epub 2020 Jul 15.
Droplet digital PCR (ddPCR) has been reported to have a superior validity over PCR with amplification-refractory mutation system (ARMS-PCR) for detecting the BRAF V600E mutation in thyroid nodule fine-needle aspiration (FNA) samples using cytological diagnosis as the reference. However, the added value of ddPCR on surgical decision-making remains to be illustrated when the technique is combined with FNA cytology.
A total of 277 consecutive patients with thyroid nodules were subjected to FNA cytology and BRAF V600E testing with ARMS-PCR. Within this patient cohort, 90 patients underwent surgical intervention with pathological diagnosis available. BRAF V600E testing with ddPCR was performed retrospectively using FNA frozen DNA specimens. The clinical validity and utility of ddPCR in comparison with ARMS-PCR were compared using surgical pathology as the reference.
Overall, 101 BRAF V600E mutations were detected by ddPCR, including five ARMS negative patients, four of whom were confirmed to have papillary thyroid cancer (PTC) by surgical pathology. Of the 90 patients with surgical pathology, which is considered the gold standard, ddPCR BRAF V600E testing yielded a sensitivity of 91.3% and specificity of 100% for PTC diagnosis, higher than that of ARMS (sensitivity 83.1%, specificity 100%). However, ddPCR only identified one more candidate patient for surgical intervention than ARMS when the techniques were combined with cytology.
This study highlighted the superior performance of ddPCR over ARMS in BRAF V600E detection from thyroid nodule FNA samples. Further studies are needed to evaluate the cost-effectiveness of replacing ARMS-PCR with ddPCR for surgical decision-making.
与扩增受阻突变系统（ARMS-PCR）相比，液滴数字 PCR（ddPCR）在甲状腺结节细针抽吸（FNA）样本中检测 BRAF V600E 突变的有效性更高，该检测以细胞学诊断为参考。然而，当该技术与 FNA 细胞学结合使用时，ddPCR 对手术决策的附加价值仍有待说明。
共对 277 例连续的甲状腺结节患者进行了 FNA 细胞学和 ARMS-PCR 的 BRAF V600E 检测。在该患者队列中，90 例患者接受了手术干预，且有病理诊断结果。使用 FNA 冷冻 DNA 标本对 ddPCR 进行了回顾性 BRAF V600E 检测。使用手术病理作为参考，比较了 ddPCR 与 ARMS-PCR 的临床有效性和实用性。
总体而言，ddPCR 检测到 101 个 BRAF V600E 突变，包括 5 个 ARMS 阴性患者，其中 4 个经手术病理证实为甲状腺乳头状癌（PTC）。在 90 例具有手术病理结果的患者中（被认为是金标准），ddPCR BRAF V600E 检测对 PTC 诊断的敏感性为 91.3%，特异性为 100%，高于 ARMS（敏感性 83.1%，特异性 100%）。然而，当将两种技术与细胞学结合使用时，ddPCR 仅比 ARMS 多识别出一个需要手术干预的候选患者。
本研究强调了 ddPCR 在甲状腺结节 FNA 样本中检测 BRAF V600E 方面优于 ARMS。需要进一步的研究来评估用 ddPCR 替代 ARMS-PCR 进行手术决策的成本效益。
