Next‐generation sequencing using tissue specimen collected with a 1.1 mm‐diameter cryoprobe in patients with lung cancer

BACKGROUND AND OBJECTIVE: Next-generation sequencing (NGS) analysis is considered standard for lung cancer diagnosis in clinical practice. Little is known about the feasibility of NGS using tumour tissue sampled with a 1.1 mm-diameter cryoprobe. We aimed to investigate the suitability of specimens obtained by transbronchial cryobiopsy (TBC) using a 1.1 mm-diameter cryoprobe for NGS analysis. METHODS: Patients with lung cancer who underwent TBC using a 1.1 mm-diameter cryoprobe for NGS testing between October 2020 and April 2023 were enrolled. A 4.0- or 3.0 mm-diameter bronchoscope with radial probe endobronchial ultrasound and virtual bronchoscopic navigation was used to detect peripheral lung lesions. All procedures were performed under fluoroscopic guidance. Data were analysed retrospectively. RESULTS: A total of 56 patients underwent TBC using a 1.1 mm cryoprobe for NGS testing, during the study period. Most patients (98%) were in the advanced stage of lung cancer (recurrent or inoperable disease of stages III or IV). The diagnostic yield of NGS for DNA and RNA sequencing was 95% each (53 of 56). Moderate bleeding was noted in three patients (5%) and none of the study patients developed life-threatening complications, such as pneumothorax or lung infection. CONCLUSION: TBC using a 1.1 mm-diameter cryoprobe is a useful and safe tool for NGS analysis, for both DNA and RNA sequencing.