Endosonography in bronchopulmonary disease

The diagnostic approach to diseases of the mediastinum is divided into two phases: (1) imaging techniques and (2) procedures for obtaining tissue samples for cytologic and histologic examination. The latter has for many years represented a considerable challenge to the clinician. Often invasive procedures in general anaesthesia as mediastinoscopy or thoracoscopy have been necessary. However, the sampling of tissue from the mediastinum has been revolutionized by EBUS and EUS, since they give access to the middle and the posterior compartment via the trachea and the oesophagus, respectively. Both EUS FNA and EBUS-TBNA of mediastinal nodes and tumors can provide a specimen adequate for interpretation in over 95% of cases with a specificity of close to 100% and a sensitivity ranging between 88% and 96%. A growing number of studies including randomized trails and meta-analyses have demonstrated a major impact of EUSFNA as well as EBUS-TBNA on management of patients with lung cancer as well as in patients with unknown lesions in the mediastinum. The aim of the present review is to discuss the current role of endosonography in bronchopulmonary diseases focusing on endosonographically guided biopsy via the esophagus, trachea and main bronchi. The concept of complete echo-endoscopic staging of lung cancer is postulated as virtually all mediastinal nodes as well as regions relevant to pulmonal medicine (liver and adrenal glands) can be reached by these two methods in combination.