Diagnostic yield of virtual bronchoscope navigation combined with radial endobronchial ultrasound guided transbronchial cryo-biopsy for peripheral pulmonary nodules: a prospective, randomized, controlled trial

Background: Transbronchial lung biopsy (TBLB) was a useful method for the diagnosis of peripheral pulmonary nodules (PPNs), but the smaller tissue samples obtained often could not meet the subsequent molecular pathological diagnosis. The purposes of this study were to assess the diagnostic yield of virtual bronchoscope navigation (VBN) combined with radial endobronchial ultrasound (rEBUS) guided transbronchial cryo-biopsy (TBCB) and to compare it with TBLB. Methods: Patients with PPNs, who planned to undergo bronchoscopy and were admitted to Henan Provincial People's Hospital and Zhoukou Central Hospital from January 1, 2020 to December 31, 2020, were divided into the TBCB group (experimental group) and TBLB group (control group) using the block randomization method. TBCB and TBLB were performed with the guidance of VBN-rEBUS. The diagnostic yields, complications, specimen surface areas, and operation times were observed. The differences between the two groups were measured by the independent sample t-test or Chi-square test. Results: A total of 152 patients were enrolled, of whom 138 completed the study, and 102 received a definite diagnosis by bronchoscopy. The diagnostic yield showed no statistically significant difference between TBCB group and TBLB group (79.1% vs. 69.0%, P=0.124). For PPNs with the diameter <2 cm, TBCB group had a significantly higher diagnostic yield than TBLB group (76.5% vs. 50.0%, P=0.022); For PPNs with eccentric and adjacent radial ultrasonic images, TBCB group also had a significantly higher diagnostic yield than TBLB group (78.1% vs. 55.9%, P=0.023). The specimen surface area of TBCB group was larger than that of TBLB group (P=0.030). The incidence of moderate bleeding in TBCB group was higher than that in TBLB group (P=0.006), but no serious complications were observed in either group. Conclusions: Although the incidence rate of moderate bleeding was higher than that of TBLB, VBNrEBUS guided TBCB is still a safe and effective diagnostic method for PPNs, and is superior to TBLB for PPNs with a diameter <2 cm or with an eccentric and adjacent radial ultrasonic image.