Accuracy of endobronchial ultrasound (EBUS) in the staging of lung cancer – A comparison of staging EBUS with postoperative pathological nodal staging

BACKGROUND: Endobronchial ultrasound-guided transbronchial fine-needle aspiration (EBUS-TBNA) has replaced mediastinoscopy as the preferred investigation for evaluating mediastinum in staging lung cancer. There is little evidence of mediastinal staging by EBUS-TBNA from India. OBJECTIVES: To study endobronchial ultrasound's diagnostic accuracy in staging lung cancer. METHODOLOGY: We retrospectively analysed patients operated on for lung cancer where EBUS was performed preoperatively for mediastinal staging. We compared the histological findings obtained from different mediastinal lymph nodes (LNs) by EBUS-TBNA with the pathology of the same LNs obtained after surgical dissection as the reference standard. RESULTS: Seventy-six patients underwent curative surgery for lung cancer. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value of EBUS-TBNA in predicting mediastinal metastasis were 93.9%, 40%, 99%, 80% and 94.6%, respectively. Of the 115 LNs sampled, EBUS-TBNA was false negative in six nodes, resulting in an up-staging of six patients. CONCLUSIONS: EBUS-TBNA has a high diagnostic accuracy for lung cancer staging.