[Role of ultrasound-guided endoscopy in the evaluation of mediastinal lesions].

The evaluation of the mediastinum is still a challenge. In most cases, a pathologic study is mandatory for therapeutic decision-making. In this setting, endoscopic ultrasonography (EUS) without and with fine needle aspiration (FNA) is currently considered as a very useful and safe non-invasive technique since it overcomes most problems raising from standard radiologic techniques at the time of obtaining histologic confirmation. Moreover, it avoids the surgical approach for diagnosis in a significant number of patients. Thus, performance characteristics (sensitivity, specificity and accuracy) of EUS FNA in the diagnosis of mediastinal lymph nodes of unknown origin are higher than 90%. The place of EUS FNA in the staging of lung cancer is not well established yet, but available data suggest that it can play a major role in patients with negative transbronchial biopsy or even in the initial evaluation regardless of CT results. Finally, recent studies also suggest that EUS FNA is the most cost-effective non-surgical technique for the study of the mediastinum.