Diagnostic Yield and Safety of Radial Probe Endobronchial Ultrasound-Guided Transbronchial Lung Cryobiopsy with a Guide Sheath in Pulmonary Lesions < 3 cm

Background/Objectives: Accurate tissue diagnosis of small pulmonary nodules remains technically challenging with conventional bronchoscopic techniques. Radial probe endobronchial ultrasound-guided transbronchial lung cryobiopsy (RP-EBUS–guided TBLC) with a guide sheath (GS) may improve diagnostic yield; however, target instability during cryobiopsy remains a limitation. We aimed to evaluate the diagnostic yield of RP-EBUS-guided TBLC with a GS for pulmonary nodules < 3 cm that were suspected of malignancy. Methods: This retrospective observational study included patients who underwent RP-EBUS-guided TBLC with a GS for lung lesions suspected of malignancy on computed tomography between 1 February 2024 and 31 December 2025 in South Korea. After the target lesion was identified, the bronchoscope was inserted and fixed within the segment; its position was maintained while RP-EBUS was withdrawn, and lesion stability during respiration was confirmed. Results: A total of 99 patients were included in the final analysis. After patients with an indeterminate diagnosis were excluded, the final diagnostic yield was 83.2%. The sensitivity and specificity were 78.9% and 100.0%, respectively. Pneumothorax occurred in 6.0% (6/99) of patients. Bleeding of grade 3 or higher was observed in two patients, and a Fogarty balloon catheter was preemptively used in five patients at the operator’s discretion. In multivariable logistic regression analysis, the computed tomography bronchus sign was identified as the only significant factor associated with pathological confirmation (odds ratio, 6.090; p = 0.005). Conclusions: RP-EBUS-guided TBLC with a GS provided an acceptable diagnostic yield and safety profile, even in small pulmonary nodules < 3 cm.