Robotic-Assisted Versus Conventional Bronchoscopy for Cryobiopsy in the Diagnosis of Interstitial Lung Disease (RAB-ILD-RCT)

Robotic-Assisted Versus Conventional Bronchoscopy for Cryobiopsy in the Diagnosis of Interstitial Lung Disease: A Randomized Controlled Trial

Interstitial lung disease (ILD) often requires histopathological confirmation when high-resolution computed tomography (HRCT) findings are inconclusive. Transbronchial lung cryobiopsy has emerged as a less invasive alternative to surgical lung biopsy, but diagnostic yield remains variable and dependent on biopsy location and procedural precision.

Robotic-assisted bronchoscopy (RAB) combined with cone-beam computed tomography (CBCT) may allow more precise navigation to target lung segments and potentially improve biopsy quality and diagnostic yield.

This multi-center, investigator-initiated randomized controlled trial will compare conventional bronchoscopy with 2D fluoroscopy guidance versus robotic-assisted bronchoscopy with CBCT guidance for transbronchial lung cryobiopsy in patients undergoing diagnostic evaluation for suspected interstitial lung disease.

Participants will be randomized in a 1:1 ratio to undergo either conventional bronchoscopy or robotic-assisted bronchoscopy. In both groups, four cryobiopsies will be obtained from two lung lobes using a 1.7 mm cryoprobe (en-bloc removal for both study arms).

The primary endpoint is the rate of definitive histological diagnosis as determined by a blinded multidisciplinary ILD board.

Study Overview

• Status: Recruiting
• Conditions: Interstitial Lung Disease (ILD); Lung Biopsy
• Intervention / Treatment: Procedure: Robotic-Assisted Bronchoscopy With Cone-Beam CT Guidance; Procedure: Conventional Bronchoscopy With Fluoroscopy Guidance

Detailed Description

Histopathologic evaluation remains a key component in the diagnosis of many interstitial lung diseases when radiological and clinical findings are inconclusive. Transbronchial lung cryobiopsy (TBLC) has increasingly replaced surgical lung biopsy due to its lower morbidity, but diagnostic yield varies widely depending on procedural technique and sampling accuracy.

Robotic-assisted bronchoscopy (RAB) offers improved catheter stability and precise navigation to peripheral lung regions. When combined with cone-beam CT (CBCT), RAB allows real-time confirmation of biopsy location, potentially improving sampling of diagnostically relevant lung parenchyma while avoiding bronchial structures.

However, the incremental diagnostic value of RAB combined with CBCT compared with conventional bronchoscopy using fluoroscopy guidance has not yet been evaluated in a randomized controlled trial.

This investigator-initiated trial aims to determine whether robotic-assisted bronchoscopy with CBCT improves the rate of definitive histological diagnosis compared with conventional bronchoscopy.

Participants will be randomized 1:1 to either:

• Conventional bronchoscopy with fluoroscopy-guided cryobiopsy
• Robotic-assisted bronchoscopy with CBCT-guided cryobiopsy

In both arms, four biopsies will be obtained from two different lung lobes using a 1.7 mm cryoprobe.

Histological specimens will be evaluated by a blinded multidisciplinary ILD board.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Thomas Gaisl, MD MPH PhD; Phone Number: +41762318339; Email: thomas.gaisl@uzh.ch

Study Locations

• Switzerland
  • Canton of Lucerne
    • Lucerne, Canton of Lucerne, Switzerland, 6000
      • Recruiting
      • Cantonal Hospital of Lucerne
      • Contact: Fiorenza Gautschi, MD; Phone Number: +41 205 22 82; Email: fiorenza.gautschi@luks.ch
  • Canton of Zurich
    • Zurich, Canton of Zurich, Switzerland, 8091
      • Recruiting
      • University Hospital Zurich
      • Contact: Carolin Steinack, MD; Phone Number: +41442553828; Email: carolin.steinack@usz.ch

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥18 years
• Clinical suspicion of interstitial lung disease requiring histological confirmation
• Non-diagnostic HRCT pattern (e.g. probable UIP or indeterminate pattern)
• Candidate for transbronchial lung cryobiopsy
• Ability to provide informed consent

Exclusion Criteria:

• Definite UIP pattern on HRCT
• Severe pulmonary hypertension
• Severe hypoxemia contraindicating bronchoscopy
• Coagulopathy or contraindication to biopsy
• Pregnancy
• Inability to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Robotic-Assisted Bronchoscopy With Cone-Beam CT Guidance; Robotic-assisted bronchoscopy using a shape-sensing robotic platform with cone-beam CT confirmation of biopsy location. Four cryobiopsies will be obtained from two lung lobes using a 1.7 mm cryoprobe.	Procedure: Robotic-Assisted Bronchoscopy With Cone-Beam CT Guidance; Robotic-assisted bronchoscopy using a shape-sensing robotic platform with cone-beam CT confirmation of biopsy location. Four cryobiopsies will be obtained from two lung lobes using a 1.7 mm cryoprobe.
Active Comparator: Conventional Bronchoscopy With Fluoroscopy Guidance; Flexible bronchoscopy with 2D fluoroscopy guidance. Four cryobiopsies will be obtained from two lung lobes using a 1.7 mm cryoprobe.	Procedure: Conventional Bronchoscopy With Fluoroscopy Guidance; Flexible bronchoscopy with 2D fluoroscopy guidance. Four cryobiopsies will be obtained from two lung lobes using a 1.7 mm cryoprobe.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Histological Diagnosis	Rate of Definitive Histological Diagnosis	Perioperative/Periprocedural

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biopsy Size	Mean cross-sectional area of cryobiopsy specimens measured in mm².	Perioperative/Periprocedural
Tissue Composition of Biopsies	Percentage composition of biopsy specimens including: Lung parenchyma; Bronchial tissue; Bronchiolar tissue	Perioperative/Periprocedural
Safety Composite	Composite safety endpoint including: Clinically significant bleeding; Pneumothorax requiring intervention; Transfer to intensive care unit	Up to 24 hours post procedure

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Radiation Exposure	Total radiation dose measured as dose-length product (DLP) or equivalent fluoroscopy dose.	Perioperative/Periprocedural
Procedure Duration	Total procedure time measured from bronchoscope insertion to bronchoscope removal.	Perioperative/Periprocedural

Collaborators and Investigators

• Sponsor: University of Zurich
• Collaborators: University Hospital, Zürich; Cantonal Hospital of Lucerne, Switzerland

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): September 1, 2027

Study Registration Dates

• First Submitted: March 18, 2026
• First Submitted That Met QC Criteria: March 24, 2026
• First Posted (Actual): March 30, 2026

Study Record Updates

• Last Update Posted (Actual): March 30, 2026
• Last Update Submitted That Met QC Criteria: March 24, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: CBCT; Cryobiopsy; Interstitial Lung Disease; Interventional Pulmonology; Robotic-assisted Bronchoscopy
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Lung Diseases, Interstitial
• Other Study ID Numbers: BASEC Nr. 2024-00684 Trial B

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No