A21-07 Utility of Adding Cryobiopsy to Forceps Biopsy During Ultrathin Bronchoscopy for Diagnosing Small Peripheral Pulmonary Lesions: A Randomized Trial

Abstract Rationale Ultrathin bronchoscopy has proven useful for diagnosing peripheral pulmonary lesions; however, its small working channel limits specimen size. The use of a 1.1-mm ultrathin cryoprobe during ultrathin bronchoscopy may overcome this limitation and improve diagnostic yield. This study aimed to compare the histological diagnostic yield of combined forceps biopsy and cryobiopsy versus forceps biopsy alone using an ultrathin bronchoscope for small peripheral pulmonary lesions. Methods In this multicenter randomized trial conducted across four institutions, patients with peripheral pulmonary lesions 30 mm in diameter were enrolled and randomly assigned to undergo either forceps biopsy (FB group) or combined forceps biopsy and cryobiopsy (FB/CB group) using a 3.0-mm ultrathin bronchoscope with virtual bronchoscopic navigation and fluoroscopic guidance. The primary endpoint was the histological diagnostic yield of biopsy specimens. Results A total of 330 patients were enrolled, and data from 328 patients (164 in each group) with peripheral pulmonary lesions (median longest diameter, 18.0 mm) were analyzed. The diagnostic yield of histological specimens was significantly higher in the FB/CB group than in the FB group (73.2% vs. 56.1%, P = 0.001). In the FB/CB group, histological diagnoses provided by FB alone and CB alone were 4.3% and 14.0%, respectively. The frequency of bleeding complications in the FB/CB and FB groups was as follows: Grade 2, 42.1% vs. 6.1%; Grade 3, 0.6% vs. 0%. Pneumothorax occurred in 2.4% of patients in each group. Conclusions Although cryobiopsy was associated with an increased risk of bleeding, the addition of cryobiopsy to forceps biopsy during ultrathin bronchoscopy significantly improved the histological diagnostic yield for small peripheral pulmonary lesions. This abstract is funded by: AMCO Inc. (provided the cryoprobe)