Pre-Conference Workshop-3

Abstract:

Convex probe endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has developed in the pursuit of accurate nodal staging of primary lung cancer and has become widely performed because of its high sensitivity and specificity, as well as its less invasive nature than conventional mediastinoscopy. The main targets are hilar and mediastinal lymph nodes that are in contact with the central airway, but also pulmonary lesions can be targeted if they are in contact. The EBUS scope can also be inserted through the esophagus to expand the range of target lesions. In addition, the obtained specimens are also known for their high compatibility with gene panel tests.
However, it is also true that EBUS scope differs from standard bronchoscopes in several ways and requires a certain amount of training to ensure the diagnostic accuracy. Target lesions are behind the central airway wall where the scope makes contact and are not visible, so it is essential to understand the anatomy to approach them quickly. It is also necessary to become familiar with the nature of the EBUS scope, which is oblique, and the EBUS screen is different from the direction and manipulation of the endoscope screen. Furthermore, once the needle is used incorrectly, the EBUS scope is subject to expensive repair costs.
On the other hand, it should be also noted that what is obtained by TBNA is cytological specimens, and even the core tissues are only cell blocks. Therefore, the diagnostic accuracy is limited for sarcoidosis, malignant lymphomas, and uncommon tumors, where tissue architecture is important for the diagnosis. To compensate for this, the efficacy of intranodal forceps biopsy and cryobiopsy has also been reported.
In this presentation, I will outline the history, basics, and applications of these convex probe EBUS-guided sampling techniques as much as possible in the time available.