Safety and Performance of Transbronchial Cryobiopsy for Parenchymal Lung Lesions.

Background Despite advances in technology, the bronchoscopic diagnosis of parenchymal pulmonary lesions (PPL) remains difficult to achieve. Transbronchial Lung Cryobiopsy (TLCB) offers the potential for larger samples with improved diagnostic yield, however, there remains a paucity of data describing its safety and utility for the diagnosis of PPL RESEARCH QUESTION: What is the safety profile of TLCB for PPL? Study design and methods An observational, retrospective, multicenter cohort study enrolling patients without endobronchial disease undergoing TLCB of PPL from 2015-2019. All procedures were performed using both rigid and flexible bronchoscopy with a flexible cryoprobe. Complication rates including bleeding and pneumothorax rates were collected. Bleeding was graded on a scale from 0 (trace) to 4 (requiring surgical intervention) with grade ≥ 3 considered clinically significant. Pneumothorax, tube thoracostomy placement, diagnostic yield and need for subsequent interventions were recorded. Results 1024 patients underwent a TLCB. 188 (18%) patients experienced bleeding and 36 (3.5%) were clinically significant. 68 (6.6%) patients developed a pneumothorax and 64 (6.3%) required drainage with tube thoracostomy. All chest drains were removed within 4 days and there were no cases of prolonged air leak. A definitive diagnosis was achieved in 932 (91%) patients. Adenocarcinoma (46%) and metastatic disease (21%) were the most common diagnoses. Interpretation TLCB has an acceptable safety profile and diagnostic yield for the evaluation of PPL in this large retrospective cohort. Prospective clinical trials are underway to further validate these findings.