Background/Objectives: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a well-established, minimally invasive method for sampling mediastinal and hilar lymph nodes. It has high sensitivity and specificity for diagnosing lymph node involvement. However, achieving a definitive cytopathological diagnosis can be challenging owing to the limited presence of atypical tumor cells. The scanning single-molecule counting (SSMC) method enables rapid measurement of target molecule expression. This study assessed the correlation between miR-200c expression measured by SSMC and lymph node metastasis confirmed by cytopathology. Methods: Following EBUS-TBNA in patients with lung cancer or suspected lung cancer, we flushed 22-gauge biopsy needles with 1 mL saline and extracted microRNA (miRNA) from the lavage fluid. The quality of SSMC results for miR-200c was evaluated and compared with that of quantitative real-time polymerase chain reaction (RT-qPCR). Results: Linear regression analysis of miR-200c between SSMC and RT-qPCR showed a statistically significant positive correlation (R2= 0.81,p< 0.0001), demonstrating the feasibility of SSMC for evaluating miRNA in lymph nodes. Based on these findings, we enrolled and analyzed 100 lymph nodes from 86 patients. High miR-200c expression detected lymph node metastasis with high sensitivity (85.7%) and specificity (83.3%) and an AUC of 0.88. No discordance was observed between the standard SSMC and rapid methods. Conclusions: The expression of miR-200c, as measured by SSMC, may serve as a biomarker for molecular nodal staging. The rapid SSMC method provides results within 30 min, significantly faster than conventional RT-qPCR, and may complement rapid on-site cytological evaluation.
背景/目的：支气管内超声引导下经支气管针吸活检（EBUS-TBNA）是一种成熟的微创方法，用于纵隔和肺门淋巴结取样。其在诊断淋巴结受累方面具有较高的敏感性和特异性。然而，由于非典型肿瘤细胞存在有限，获得明确的细胞病理学诊断可能具有挑战性。扫描单分子计数（SSMC）方法能够快速测量目标分子表达。本研究评估了通过SSMC测量的miR-200c表达与细胞病理学证实的淋巴结转移之间的相关性。方法：对肺癌或疑似肺癌患者进行EBUS-TBNA后，用1 mL生理盐水冲洗22号活检针，并从灌洗液中提取微RNA（miRNA）。评估了miR-200c的SSMC结果质量，并与实时定量聚合酶链反应（RT-qPCR）进行了比较。结果：SSMC与RT-qPCR对miR-200c的线性回归分析显示存在统计学显著的正相关（R²=0.81，p<0.0001），证明了SSMC评估淋巴结中miRNA的可行性。基于这些发现，我们纳入并分析了来自86名患者的100个淋巴结。高miR-200c表达检测淋巴结转移具有高敏感性（85.7%）和高特异性（83.3%），AUC值为0.88。标准SSMC方法与快速方法之间未观察到不一致。结论：通过SSMC测量的miR-200c表达可作为分子淋巴结分期的生物标志物。快速SSMC方法可在30分钟内提供结果，显著快于传统RT-qPCR，并可能补充快速现场细胞学评估。
肿瘤(癌症)患者之家