Akca Yasemin, Erkilic Suna
Department of Pathology, Faculty of Medicine, Gaziantep University, Gaziantep, Turkey.
J Cytol. 2024 Jul-Sep;41(3):171-175. doi: 10.4103/joc.joc_116_23. Epub 2024 Jul 18.
Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung carcinomas (NSCLC) are a frequent class of driver mutations, and tyrosine kinase inhibitor (TKI) therapy provides considerable clinical benefits. Using the most effective and also easiest method for EGFR analysis is cost-effective and time-saving. In this study, we aimed to determine which method could be more effective by comparing the incidences of EGFR mutations in cytological and histological samples which were obtained by different methods also, whether there was a difference in the incidences of EGFR mutations between the primary foci, mediastinal lymph nodes, and distant metastatic foci.
We retrospectively reviewed 420 cases of cytological materials, small biopsies, and surgical samples reported as NSCLC underwent EGFR analysis in our department between 2016 and 2022. We collected the data and interpreted the results from two different perspectives.
We identified 36 EGFR mutations in 362 biopsies (9.94%) and 17 in 58 cytology samples (29.31%). There is a significant difference between the two methods ( = 0.01*). We observed 38 EGFR mutations in 320 primary foci (11.87%), 7 EGFR mutations in 36 mediastinal or subcarinal lymph nodes (19.44%), and 8 EGFR mutations in 64 distant metastatic foci (12.50%). A significant difference was also observed in pleural samples ( = 0.005*).
We observed more successful results with cell blocks obtained from liquid-based cytological specimens than with formalin-fixed, paraffin-embedded tissues obtained from resection or otherwise in our clinical routine. Our study results highlight the benefits of cytological specimens in molecular treatments and current therapy modalities.
非小细胞肺癌（NSCLC）中的表皮生长因子受体（EGFR）突变是一类常见的驱动突变，酪氨酸激酶抑制剂（TKI）治疗可带来显著的临床益处。采用最有效且最简单的EGFR分析方法具有成本效益且节省时间。在本研究中，我们旨在通过比较不同方法获取的细胞学和组织学样本中EGFR突变的发生率，确定哪种方法更有效，以及原发性病灶、纵隔淋巴结和远处转移病灶之间EGFR突变发生率是否存在差异。
我们回顾性分析了2016年至2022年期间在我科进行EGFR分析的420例报告为NSCLC的细胞学材料、小活检标本和手术样本。我们从两个不同角度收集数据并解读结果。
我们在362例活检标本中鉴定出36例EGFR突变（9.94%），在58例细胞学样本中鉴定出17例（29.31%）。两种方法之间存在显著差异（P = 0.01*）。我们在320个原发性病灶中观察到38例EGFR突变（11.87%），在36个纵隔或隆突下淋巴结中观察到7例EGFR突变（19.44%），在64个远处转移病灶中观察到8例EGFR突变（12.50%）。在胸膜样本中也观察到显著差异（P = 0.005*）。
在我们的临床实践中，我们观察到从液基细胞学标本获得的细胞块比从切除或其他方式获得的福尔马林固定、石蜡包埋组织有更成功的结果。我们的研究结果突出了细胞学标本在分子治疗和当前治疗模式中的益处。
