Endobronchial Ultrasound for the Screening of Pulmonary Embolism in Patients with Suspected Lung Cancer: A Prospective Cohort Study

Abstract

Background: Patients with lung cancer exhibit increased risk of pulmonary embolism (PE). While the contrast phase of computed tomography of the chest in the diagnostic work-up of suspected chest malignancy does not allow reliable detection of PE, it may be feasible to screen for present PE during endobronchial ultrasound (EBUS) examination.

Objectives: The aim of this study was to establish if screening during EBUS for PE in patients with suspected lung cancer is feasible and if positive findings are predictive of PE.

Methods: Patients undergoing EBUS due to suspicion of malignancy of the chest were prospectively enrolled. The pulmonary arteries were assessed during EBUS using a standardized protocol. Patients in whom PE suspicion was raised were referred to confirmatory imaging.

Results: From December 2020 to August 2021, 100 patients were included. Median time for vascular assessment during EBUS was 2 min (Q1-Q3: 1-3 min). EBUS identified two suspected PEs (2%), and the number needed to scan was 50. The positive predictive value of EBUS for PE was 100%.

Conclusion: EBUS for PE screening seems feasible and with limited time use. The PPV of positive findings for the diagnosis of PE is high, but the utility is somewhat limited by a high number needed to scan even in a high-risk population. Based on our findings, we believe that EBUS assessment of the pulmonary vasculature may have a role as a routine screening tool for PE. The assessment for PE should be implemented in EBUS training programmes, as operators should be able to recognize incidental PEs.

Keywords: Endobronchial ultrasound examination; Lung cancer; Pulmonary embolism; Screening.