Efficacy of Radial Endobronchial Ultrasound (R-EBUS) guided transbronchial cryobiopsy for peripheral pulmonary lesions (PPL...s): A systematic review and meta-analysis.

Background: Transbronchial lung cryobiopsy (TBLC) is frequently described for the diagnosis of diffuse parenchymal lung diseases (DPLD). A few studies have reported transbronchial cryobiopsy for the diagnosis of peripheral pulmonary lesions (PPL...s). We aimed to study the utility and safety of transbronchial cryobiopsy for the diagnosis of PPL...s.

Methods: We performed a systematic search of the PubMed and Embase databases to extract the relevant studies. We then performed a meta-analysis to calculate the diagnostic yields of transbronchial cryobiopsy and bronchoscopic forceps biopsy.

Results: Following a systematic search, we identified nine relevant studies (300 patients undergoing cryobiopsy). All used Radial Endobronchial Ultrasound (R-EBUS) for PPL localization. The pooled diagnostic yield of transbronchial cryobiopsy was 77% (95% CI, 71%...84%) (I^2=38.72%, p=0.11). The diagnostic yield of forceps biopsy was 72% (95% CI, 60%...83%) (I^2=78.56%, p<0.01). The diagnostic yield of cryobiopsy and forceps biopsy was similar (RR 1.05, 95% CI 0.96...1.15), with a 5% risk difference for diagnostic yield (95% CI, ...6% to 15%). There was significant heterogeneity (I^2=57.2%, p=0.017), and no significant publication bias. One severe bleeding and three pneumothoraxes requiring intercostal drain (ICD) placement (major complication rate 4/122, 1.8%) were reported with transbronchial cryobiopsy.

Conclusions: R-EBUS guided transbronchial cryobiopsy is a safe and efficacious modality. The diagnostic yields of TBLC and forceps biopsy are similar. More extensive multicentre randomized trials are required for the further evaluation and standardization of transbronchial cryobiopsy for PPL...s.