Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure that has revolutionized the diagnosis and staging of lung cancer. The goal of the present study was to investigate the yield and applicability of molecular testing in the specimens obtained by EBUS-TBNA from patients with advanced non-small cell lung cancer (NSCLC), comparing the results with a series of patients who underwent diagnostic surgical procedures in the same institution.
The study followed 306 consecutive patients with clinically diagnosed primary lung cancer who had the EBUS-TBNA procedure. EGFR and KRAS mutations were evaluated on cytologic specimens by Sanger sequencing and Cobas real-time polymerase chain reaction, whereas ALK rearrangement was tested by fluorescence in situ hybridization. The results were compared with those obtained from a series of 1,000 NSCLC surgical samples routinely analyzed.
Molecular testing was possible in 96.9% of the samples obtained by EBUS-TBNA. EGFR (exons 18-21) mutations were found in 16.9%, KRAS mutation (exons 2-3) in 31.6%, and ALK rearrangement in 3.9% of the cases. In the surgical series, the mutations' distribution were 14.8%, 29.0%, and 3.4%, respectively. There were no statistical differences between the two series.
Our study demonstrates that EBUS-TBNA can be effectively used not just for diagnosis but also for complete mutational testing.
研究数据来自306例临床诊断为原发性肺癌接受EBUS-TBNA的患者。细胞学标本使用Sanger测序和Cobas real-time PCR检测EGFR和KRAS突变，FISH检测ALK重排。结果与一个含1000例外科标本的常规分析结果系列相比较。96.9%的EBUS-TBNA标本可用于分子检测。16.9%检测到EGFR（18-21外显子）突变，31.6%检测到KRAS突变（2-3外显子），3.9%检测到ALK重排。外科标本系列的阳性率分别为14.8%，29.0%，3.4%。这两个系列没有统计学差别。