Utilizing Endobronchial Ultrasound With Fine-Needle Aspiration to Obtain Tissue for Molecular Analysis A Single-Center Experience

Background: Lung cancer is the leading cause of cancer deaths worldwide, with the majority of patients presenting with advanced disease for which surgery is not an option. Recently, a number of genetic mutations have been identified that predict response to chemotherapy, making the acquisition of tissue for molecular analysis important for treatment planning. It has previously been demonstrated that samples obtained using endobronchial ultrasound fine-needle aspiration (EBUS-FNA) are adequate for this analysis. This is the first report on the use of EBUS-FNA specimens for analysis of the epithelial mesenchymal transition (EMT) pathway. Methods: A total of 74 consecutive patients with known or suspected lung cancer undergoing EBUS for diagnosis and/or staging were enrolled in this study. Total RNA was isolated from the FNA specimens, reverse transcribed, and analyzed for expression of a panel of genes associated with EMT using a probe-based real-time quantitative polymerase chain reaction. Results: A total of 150 lymph nodes were sampled from the 74 patients who participated in the study. There was adequate tissue to perform real-time polymerase chain reaction in 130 (86%) of the nodes. Conclusions: EBUS-FNA samples are adequate for analysis of novel markers and pathways, including EMT, which may predict prognosis, responsiveness to therapy, and provide potential targets for new drug development. As the treatment of lung cancer shifts toward a more personalized approach, EBUS-FNA will likely play a central role in tissue acquisition for diagnosis, staging, and molecular analysis.