Recent advances in endobronchial ultrasound-guided transbronchial needle aspiration.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive modality for sampling of mediastinal and hilar lymph nodes as well as pulmonary lesions adjacent to the airway. Guidelines for staging of lung cancer suggest that EBUS-TBNA should be considered the best first test of nodal staging for radiologically abnormal lymph nodes that are accessible by this approach. The application of EBUS-TBNA in pulmonary medicine and thoracic oncology is expanding with its role in the diagnosis of sarcoidosis, lymphoma, and tuberculosis. Especially for patients with early-stage sarcoidosis with adenopathy and minimal changes in the lung parenchyma, EBUS-TBNA has a significantly higher diagnostic yield compared to the conventional bronchoscopic modalities. Multidirectional analysis of samples obtained by EBUS-TBNA has allowed assessment of lymphoma and molecular analysis in lung cancer. Histological evaluation with immunohistochemistry, flow cytometry, fluorescence in situ hybridization, and chromosome analysis can be performed if good-quality samples can be obtained. Molecular analyses such as identification of epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) fusion gene detection now are being performed routinely with good sampling. One of the advantages of EBUS-TBNA is the ability to perform repeat procedures in a minimally invasive way. Restaging of the mediastinum after induction therapy can be done safely and with ease compared to repeat surgical procedures. With improvement in molecular analysis technology, comprehensive gene expression analysis will become important in the management of patients with lung cancer. Further advances in EBUS technology and needles for tissue sampling likely will help bronchoscopists to acquire ideal tissue.