Transbronchial Lung Cryobiopsy Performed with Cone Beam Computed Tomography Guidance Versus Fluoroscopy: A Retrospective Cohort Review

The Diagnostic Efficiency and Safety of Transbronchial Lung Cryobiopsy Using 1.1-mm Cryoprobe in Diagnosing Interstitial Lung Disease

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is increasingly used to diagnose interstitial lung disease (ILD). The 1.1-mm cryoprobe has recently been available in clinical practice. The diagnostic yield and safety of TBLC using a 1.1-mm cryoprobe need to be confirmed.

METHODS

A prospective, randomized controlled trial was conducted in patients with suspected ILD and randomly assigned to 1.1-mm and 1.9-mm cryoprobe groups. The primary outcome was the diagnostic yield of multidisciplinary discussion. Secondary outcomes were sample quality and incidence of complications. The tension and stress effects during TBLC onto the target lobe caused by 1.1-mm and 1.9-mm cryoprobes were also evaluated using finite element analysis.

RESULTS

A total of 224 patients were enrolled. No significant differences were observed in the diagnostic yield (80.4% vs. 79.5%, p = 0.845) and sample quality scores (5.73 ± 0.64 vs. 5.66 ± 0.77; p = 0.324) between the 1.9-mm cryoprobe group and 1.1-mm cryoprobe group. The average surface areas of samples in 1.1-mm cryoprobe group were smaller, while no difference in sample weights was observed. A decreased incidence of moderate bleeding was found in the 1.1-mm cryoprobe group (17.0% vs. 6.2%, p = 0.027), while there was no difference in the incidence of the pneumothorax, there was a trend to higher rate of pneumothorax in 1.1-mm group. In finite element analysis, the 1.1-mm cryoprobe required the largest tension and produced the largest stress.

CONCLUSION

Compared with a 1.9-mm cryoprobe, there was no difference in specimen quality or diagnostic rate but smaller sample size with a 1.1-mm cryoprobe. There was a decreased risk of moderate bleeding, but a trend towards increased risk for pneumothorax with 1.1-mm cryoprobe.

TRAIL REGISTRATION

Clinicaltrials.gov identifier NCT04047667; registered August 4, 2019.

Cone-Beam Computed Tomography Improves Location of Transbronchial Cryobiopsy in Interstitial Lung Disease with Limited Extent

INTRODUCTION

Transbronchial lung cryobiopsy has been recommended as an acceptable alternative to surgical approach for making a histopathological diagnosis in patients with interstitial lung disease (ILD) of undetermined type. In limited diseases (especially if distributed along the subpleural region), sampling the specific area in which the pathological process is more represented could be challenging. Aim of the study was to determine the potential benefit of utilizing cone-beam computed tomography-guided cryobiopsy in patients with limited extent of ILD on CT scan and determine the single impact of each sequential biopsy progressively increasing the total number of biopsies.

METHODS

This study is a prospective analysis of patients with undetermined ILD and CT scan extent <15% undergoing cone-beam CT-guided cryobiopsy. Each biopsy sample was collected and processed individually and pathologic interpretations were performed sequentially with the pathologist reformulating a new report with the addition of each sample (cumulative yield).

RESULTS

Thirty six patients were enrolled. Pathological diagnostic yield was >90%, with almost 80% of diagnostic samples being the first one; when a second biopsy was performed, mean diagnostic yield increased with only a moderately significant difference. No severe adverse events were observed; pneumothorax was documented in 27.8% of the cases.

CONCLUSION

Sequential individual collection and pathologic interpretation of each biopsy sample has confirmed the possibility of obtaining a diagnostic specimen at the first pass if transbronchial cryobiopsy is performed under cone-beam CT.