Advances in interventional diagnostic bronchoscopy for peripheral pulmonary lesions

ABSTRACT

Introduction: The incidence of peripheral pulmonary lesions (PPLs) is growing following the adoption of lung cancer screening by low-dose chest CT. Although CT-guided transthoracic needle aspiration has been the standard method to diagnose PPLs, the field of interventional bronchoscopy is rapidly advancing to overcome complications of the transthoracic approach yet maintain the yield.

Areas covered: This article reviews the clinical evidence of recent emerging interventional bronchoscopic techniques for diagnosis of PPLs.

Expert opinion: Recent advances in interventional bronchoscopy contribute to not only the safety of transbronchial approaches to PPLs but also the higher diagnostic yield. To perform accurate sampling of PPLs, bronchoscopists must select the correct airway, approach the target as close as possible, and confirm the location of the target before sampling. These key steps can be assisted by recently developed technologies. However, it is important for bronchoscopists to understand the strengths and limitations of these emerging technologies.

KEYWORDS:

• Bronchoscopy
• interventional pulmonology
• peripheral pulmonary lesions
• thin bronchoscope
• virtual navigation bronchoscopy
• electromagnetic navigation bronchoscopy
• radial probe endobronchial ultrasound
• cone-beam computed tomography
• robotic bronchoscopy

Article highlights

• Innovative bronchoscopic techniques have evolved over the last decade to diagnose PPLs more accurately.

• Conventional bronchoscopy is limited in diagnosing PPLs, though remains effective for diagnosing bronchoscopically visible lesions. The limitations of conventional bronchoscopy might be the selectability of target bronchi and uncertainty of reaching the target lesion.

• Although CT-guided transthoracic needle aspiration (CT-TTNA) is more accurate than conventional bronchoscopy for the diagnosis of PPLs, the complication rate of CT-TTNA is high.

• Thin/ultrathin bronchoscopes allow better maneuverability and greater angulation of the tip, allowing access to PPLs in smaller airways. Their small working channels are a shortcoming.

• Radial probe endobronchial ultrasound (RP-EBUS) improves diagnostic yield by confirming the location of the target lesion with low complication rates. RP-EBUS itself is not a navigational tool.

• Navigational bronchoscopy, including virtual navigation bronchoscopy (VBN) and electromagnetic navigation bronchoscopy (ENB), is a technique that utilizes 3-D reconstructions of pre-procedure CT images that are subsequently mapped to the bronchoscope position to guides the bronchoscopist to the target lesion. Neither VBN nor ENB offer real-time imaging.

• Bronchoscopic transparenchymal nodule access (BTPNA)/Transbronchial access tool (TBAT) are new emerging techniques that are used with navigational assistance to access PPLs without a bronchus leading to the target. Their safety should be verified in further trials with larger sample sizes.

• Cone-beam computed tomography (CBCT) allows three-dimensional confirmation of the location of the biopsy site prior to the target sampling during bronchoscopy.

• Robotic bronchoscopy is a new concept to approach PPLs using a small bronchoscope manipulated by a controller. It requires further study to establish its utility.

Declaration of interest

K Yasufuku has received educational and research grant from Olympus Corporation. K Yasufuku is also a consultant for Olympus America Inc, Intuitive Surgical Inc, Auris Surgical Robotics, Medtronic, Johnson and Johnson. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.