Transbronchial biopsy results according to diffuse interstitial lung disease classification. Cryobiopsy versus forceps: MULTICRIO study.

Background: In recent years, transbronchial cryobiopsy (TBCB) has come to be increasingly used in interventional pulmonology units as it obtains larger and better-quality samples than conventional transbronchial lung biopsy (TBLB) with forceps. No multicenter studies have been performed, however, that analyse and compare TBCB and TBLB safety and yield according to the interstitial lung disease (ILD) classification.

Objectives: We compared the diagnostic yield and safety of TBCB with cryoprobe sampling versus conventional TBLB forceps sampling in the same patient.

Method: Prospective multicenter clinical study of patients with ILD indicated for lung biopsy. Airway management with orotracheal tube, laryngeal mask and rigid bronchoscope was according to the protocol of each centre. All procedures were performed using fluoroscopy and an occlusion balloon. TBLB was followed by TBCB. Complications were recorded after both TBLB and TBCB.

Results: Included were 124 patients from 10 hospitals. Airway management was orotracheal intubation in 74% of cases. Diagnostic yield according to multidisciplinary committee results for TBCB was 47.6% and for TBLB was 19.4% (p<0.0001). Diagnostic yield was higher for TBCB compared to TBLB for two groups: idiopathic interstitial pneumonias (IIPs) and ILD of known cause or association (OR 2.5; 95% CI: 1.4-4.2 and OR 5.8; 95% CI: 2.3-14.3, respectively). Grade 3 (moderate) bleeding after TBCB occurred in 6.5% of patients compared to 0.8% after conventional TBLB.

Conclusions: Diagnostic yield for TBCB was higher than for TBLB, especially for two disease groups: IIPs and ILD of known cause or association. The increased risk of bleeding associated with TBCB confirms the need for safe airway management and prophylactic occlusion-balloon use.

Trial Registration: clinicaltrials.gov identifier: NCT02464592.