Complete “medical mediastinoscopy“ under conscious sedation: A prospective blinded comparison of endoscopic and endobronchial ultrasound to bronchoscopic fine needle aspiration for malignant mediastinal lymph nodes

Background: We have previously reported a retrospective study suggesting endobronchial ultrasound (EBUS) and endoscopic ultrasound (EUS) are superior to blind bronchoscopic (“Wang“) FNA for detection of malignant mediastinal lymph nodes (Wallace et al. DDW 2005). We now report a prospective, blinded trial comparing the accuracy and feasibility of each modality.

Methods: Patients presenting with lung tumors and/or enlarged mediastinal lymph nodes underwent combined EUS-FNA, EBUS-FNA and bronchoscopy-FNA, under a single conscious sedation. EBUS was performed by pulmonologists who had previously completed training in EBUS-FNA. Three experienced endosonographers performed EUS-FNA, blinded to the results of bronch and EBUS. Patients without metastatic disease on all three procedures underwent surgery.

Results: Sixty patients have been evaluated. Thirty nine malignant lymph nodes were detected in 29 patients by at least one procedure. The detection accuracy for each procedure and combination of procedures on a a per-patient basis in table 1.

The combination of EUS and EBUS detected all patients with malignant lymph nodes except one which had a level 6 (anterior to aortic arch) node only detected by thoracoscopy (Sensitivity 97%, Specificity 100%). EBUS detected lymph nodes in the anterior (AJCC level 2, 3, 4) mediastinum and subcarina, whereas EUS detected lymph nodes lateral to the trachea (level 2L/R, 4L/R), aortopulmonary window, subcarina and lower mediastinum (level 8–9).

Conclusions: When used in combination, EUS and EBUS allow near-complete, non-surgical staging of the mediastinum under conscious sedation in patients with lung tumors and enlarged mediastinal lymph nodes.

Procedure	Sensitivit	Specificit
Bronch-FNA	45%	100%
EUS-FNA	83%	100%
EBUS-FNA	86%	100%
Bronch+EUS	86%	100%
EBUS+EUS	97%	100%