FROSTBITE-2 trial: Cryobiopsy vs forceps for transbronchial lung biopsy

Results from the open-label, multicenter, randomized FROSTBITE-2 (NCT05751278) trial, comparing a 1.1-mm cryoprobe (n = 250) vs 2.0-mm forceps (n = 250) for transbronchial biopsy in patients referred for biopsy for lung transplantation , lung nodule or mass, or diffuse parenchymal lung disease (DPLD), were published in JAMA by Thiboutot et al. The primary outcome was overall diagnostic yield based on transbronchial biopsy, as assessed by the central pathology core. 

Key data: The primary outcome of diagnostic yield was higher with the cryoprobe vs forceps (88.6% vs 78.8%; absolute difference, 9.8%; 95% confidence interval [CI], 3.3%–16.3%; p = 0.003). The cryoprobe vs forceps diagnostic yield was greater in the lung transplant (96.0% vs 88.7%; p = 0.03) and lung nodule or mass (83.2% vs 70.1%; p = 0.04) subgroups but not in DPLD (72.0% vs 62.5%; p = 0.55). Cryobiopsy yielded larger specimen size (p < 0.001) and less crush artifact (p < 0.001) vs forceps. Combined Grade ≥2 pneumothorax, Grade 3–4 bleeding, and respiratory failure occurred in 0.0% of patients in the cryobiopsy group vs 1.6% of patients in the forceps group. 

Key learning: Transbronchial biopsy with a 1.1-mm cryoprobe demonstrated significantly higher diagnostic yield and a favorable safety profile compared with standard 2.0-mm forceps, supporting its adoption for bronchoscopic lung biopsy across multiple indications.