Utility and safety of endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC): A systematic review and meta-analysis

Background Modalities to improve tissue acquisition during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) have been investigated. Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC) is a modality to obtain larger histological samples by inserting a cryoprobe into the mediastinal lesion. We aimed to study the diagnostic yield and safety of EBUS-TMC. 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 yield of EBUS-TMC and compare it with EBUS-TBNA. Results Following a systematic search, we identified 14 relevant studies (869 patients undergoing EBUS-TMC and EBUS-TBNA). We then performed a meta-analysis of the diagnostic yield of EBUS-TMC and EBUS-TBNA from studies wherein both procedures were performed. The pooled diagnostic yield of EBUS-TMC was 92% (95% confidence interval [CI], 89%–95%). The pooled diagnostic yield of EBUS-TBNA was 81% (95% CI, 77%–85%). The risk difference in yield was 11% (95% CI, 6%–15%, I2 = 0%) when EBUS-TMC and EBUS-TBNA were compared. The only complication reported commonly with EBUS-TMC was minor bleeding. The complication rate was comparable with EBUS-TBNA. Conclusion EBUS-TMC provides a greater diagnostic yield with a similar risk of adverse events compared to EBUS-TBNA. Future studies are required to clearly establish which patients are most likely to benefit from this modality.