Transbronchial lung cryobiopsy guided with radial mini-probe EBUS for diagnosing peripheral lung lesions suspected of malignancy

Introduction: Transbronchial lung cryobiopsy (TBLC) is commonly used in diagnosing interstitial lung diseases. There are only few papers presenting the utility of radial mini-probe EBUS guided TBLC. And also little is known about a role of this technique in diagnosing peripheral lung lesions (PLL) suspected of malignancy. Objectives: Prospective, observational single center study to evaluate diagnostic efficacy of radial-EBUS guided TBLC of PLL in obtaining histological diagnosis and lung cancer (LC) molecular subtyping. Methods: In patients with PLL suspected of malignancy and after prior negative cytological attempt TBLC guided by radial-EBUS without a guide sheath was performed. Two to three biopsies with freezing time 5-8 seconds were taken. Procedure was performed under conscious sedation, without tracheal intubation and balloon bronchial blockers were no routinely used. If LC was diagnosed material was sent for molecular testing. Results: From January 2018 to June 2019 – 44 patients (M: 31, F: 13) of mean (SD) age 65.5 (9.8) years were included. Histopathology was conclusive in 41 (93%) patients: Adenocarcinoma (21), SCC (15), No Otherwise Specified (NOS) LC (2), lymphoma (1), inflammatory tumor (1) and silicosis (1). Molecular subtyping was performed in 9 (60%) of SCC and 15 (88%) of Adenocarcinoma and NOS. Results were positive for EGFR (11.8%), ALK (9%), PDL1 (11.1%). No serious complications were noted. In one case moderate bleeding after biopsy was managed endoscopically. Conclusions: TBLC under conscious sedation guided by radial mini-probe EBUS seems to be reasonable, efficient and safe method for diagnosing PLL and molecular subtyping of LC.