Abstract
BACKGROUND: Peripheral pulmonary lesions (PPLs) are being discovered more frequently. We investigated efficiency, safety, and influencing factors in radial probe endobronchial ultrasound with distance measurement (rEBUS-D) using a thin bronchoscope during transbronchial biopsy (TBB) for the diagnosis of malignant PPLs. METHODS: Patients with PPLs who underwent rEBUS were retrospectively analyzed. Cases with rEBUS-D and a gold-standard final diagnosis were considered. RESULTS: rEBUS was completed in 589 cases; 328 were analyzed. The lesion discovery rate was 85.06%; the overall rEBUS-D-TBB diagnostic rate was 54.88%. There were 193 cases of malignant tumors. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of rEBUS-D-TBB in the diagnosis of malignant PPLs were 63.73%, 100%, 100%, 65.85%, and 78.40%, respectively. Single- and multi-factor analyses showed that lesion size, ultrasound probe position, and a positive bronchus sign on thoracic computed tomography (CT) were significant factors influencing diagnosis (all P=0.000); probe position and the bronchus sign were independent influencing factors. The effect of lesion distribution on diagnosis was not significant. In seven cases, postoperative pathology showed mixed tumors. Two cases of malignant tumors were combined with benign pathology; rEBUS-D-TBB did not suggest two pathologies. Thirteen cases had 50-100 mL of blood loss (3.96%); no pneumothorax or infection was observed. CONCLUSIONS: rEBUS-D-TBB had high sensitivity, 100% specificity, excellent safety, and a lower cost than rEBUS-GS-TBB in the diagnosis of malignant PPLs. Larger lesions, a positive bronchus sign on CT, and ultrasound probe position at the lesion's center yielded higher diagnostic rates.