Endobronchial ultrasound-transbronchial needle aspiration for mediastinal staging of non-small cell lung cancer: variability of results and perspectives.

The remarkable value of endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) for mediastinal staging of non-small cell lung cancer (NSCLC) is recognized worldwide. Reports from different centers however show considerable variation of EBUS-TBNA performance in terms of diagnostic yield, sensitivity and negative predictive value (NPV). Interpretation of EBUS-TBNA diagnostic efficacy requires clarifying whether the technique is used for purely diagnostic purpose or mediastinal staging, recognizing that different study groups may be inherently heterogeneous and that numerous factors may impact on the procedure outcomes. Review of these factors indicates that the prevalence of N2/N3 disease, the thoroughness of mediastinal sampling and >3 needle passes per target lymph node (LN) [in the absence of rapid on-site evaluation (ROSE)] influence the procedure outcomes, while many details in the sample preparation technique are unlikely to impact on the results and should be left to the proceduralists' preference. Generalized use of a standardized database for prospective collection of relevant EBUS-TBNA data would allow reporting institutional results by sub-groups of N2/N3 disease prevalence and thoroughness of staging, and would help establishing quality standards for the procedure.