Cryobiopsy-Based Tri-Modality Sampling Using an Ultrathin Bronchoscope for the Diagnosis of Peripheral Lung Lesions: A Prospective Observational Study.

Introduction: Transbronchial lung biopsy using radial probe endobronchial ultrasound (RP-EBUS) is an important modality for diagnosing peripheral lung lesions (PLLs), but unmet needs remain. This study evaluates the diagnostic yields and safety of cryobiopsy-based tri-modality sampling using an ultrathin bronchoscope (UTB) with RP-EBUS for diagnosing PLLs.

Methods: This prospective observational pilot study was conducted from November 2023 to January 2024, and included patients with PLLs ≤30 mm in diameter. Bronchoscopic procedures were performed using a UTB guided by RP-EBUS. Tri-modality sampling was sequentially conducted using cryobiopsy, forceps biopsy, and transbronchial needle aspiration (TBNA). The primary outcome was cumulative diagnostic yield, and secondary outcomes included the diagnostic yield of each modality and adverse events.

Results: Fifty patients with PLLs, with a median diameter of 20.3 mm, were included. A bronchus sign was present in 66% of cases, and lesions were invisible on RP-EBUS in three instances. The overall cumulative diagnostic yield was 78%. The diagnostic yields were 78.7%, 66.7%, and 54.2% for cryobiopsy, forceps biopsy, and TBNA, respectively. Adding forceps biopsy to cryobiopsy improved the diagnostic yield by 4%, from 74% to 78%, and increased sensitivity for malignancy by 5.1%, from 84.6% to 89.7%. TBNA did not provide any additional improvement in diagnostic yield or sensitivity to malignancy. Bleeding occurred in 68% of the patients, with 28% experiencing grade 3 bleeding, all managed without life-threatening complications.

Conclusion: Cryobiopsy-based combination sampling modality using UTB is feasible and safe for diagnosing PLLs, offering high diagnostic yield and improved sensitivity for malignancy.