Development of the Korean Association for Lung Cancer Clinical Practice Guidelines: Recommendations on Radial Probe Endobronchial Ultrasound for Diagnosing Lung Cancer - An Updated Meta-Analysis

Can intraoperative improvement of radial endobronchial ultrasound imaging enhance the diagnostic yield in peripheral pulmonary lesions?

BACKGROUND

Data regarding the diagnostic efficacy of radial endobronchial ultrasound (R-EBUS) findings obtained via transbronchial needle aspiration (TBNA)/biopsy (TBB) with endobronchial ultrasonography with a guide sheath (EBUS-GS) for peripheral pulmonary lesions (PPLs) are lacking. We evaluated whether intraoperative probe repositioning improves R-EBUS imaging and affects diagnostic yield and safety of EBUS-guided sampling for PPLs.

METHODS

We retrospectively studied 363 patients with PPLs who underwent TBNA/TBB (83 lesions) or TBB (280 lesions) using EBUS-GS. Based on the R-EBUS findings before and after these procedures, patients were categorized into three groups: the improved R-EBUS image (n = 52), unimproved R-EBUS image (n = 69), and initial within-lesion groups (n = 242). The impact of improved R-EBUS findings on diagnostic yield and complications was assessed using multivariable logistic regression, adjusting for lesion size, lesion location, and the presence of a bronchus leading to the lesion on CT. A separate exploratory random-forest model with SHAP analysis was used to explore factors associated with successful repositioning in lesions not initially "within."

RESULTS

The diagnostic yield in the improved R-EBUS group was significantly higher than that in the unimproved R-EBUS group (76.9% vs. 46.4%, p = 0.001). The regression model revealed that the improvement in intraoperative R-EBUS findings was associated with a high diagnostic yield (odds ratio: 3.55, 95% confidence interval, 1.57-8.06, p = 0.002). Machine learning analysis indicated that inner lesion location and radiographic visibility were the most influential predictors of successful repositioning. The complication rates were similar across all groups (total complications: 5.8% vs. 4.3% vs. 6.2%, p = 0.943).

CONCLUSIONS

Improved R-EBUS findings during TBNA/TBB or TBB with EBUS-GS were associated with a high diagnostic yield without an increase in complications, even when the initial R-EBUS findings were inadequate. This suggests that repeated intraoperative probe repositioning can safely boost outcomes.

Efficacy and safety of radial probe endobronchial ultrasound-guided biopsy for peripheral lung lesions in chronic obstructive pulmonary disease patients

Background

Chronic obstructive pulmonary disease (COPD) is associated with frequent complications after transthoracic biopsy. Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) is widely used to diagnose peripheral pulmonary lesions (PPLs). However, the efficacy and safety of this procedure for the diagnosis of PPLs in patients with COPD remain poorly understood. We investigated the usefulness of RP-EBUS-TBLB for diagnosing PPLs in patients with COPD.

Methods

This retrospective observational study aimed to identify clinical outcomes of RP-EBUS-TBLB in patients with COPD. A total of 175 patients with COPD and 439 patients without COPD were included in this study. RP-EBUS-TBLB was performed without fluoroscopy using a guide sheath.

Results

The overall diagnostic accuracies in patients with COPD and without COPD were 80.6% (141/175) and 78.8% (346/439), respectively. There was no significant difference in the diagnostic yield based on the severity of airflow limitation (80.0%, 81.4%, and 79.2% for mild, moderate, and severe to very airflow limitations, respectively; P=0.97). In patients with COPD, diagnostic yields for malignant and benign lesions were 85.6% (95/111) and 71.9% (46/64). In multivariable analyses, larger lesion size [≥30 mm; odds ratio (OR), 2.86; 95% confidence interval (CI): 1.10-7.45; P=0.03] and within the lesion on EBUS image (OR 9.29; 95% CI: 3.79-22.79; P<0.001) were associated with diagnostic success in patients with COPD, whereas lesion location of upper lobe (OR, 0.36; 95% CI: 0.14-0.92; P=0.03) were associated with diagnostic failure. The overall complication rate in our study was 7.4% (13/175) in patients with COPD. Pneumothorax occurred in 4.6% (8/175), and chest tube insertion was needed in 1.7% (3/175) of the patients.

Conclusions

RP-EBUS-TBLB can be used as an appropriate method to diagnose PPLs in patients with COPD. The size of the lesion (≥30 mm) and having the probe within the lesion were important for successful diagnosis. The location of the lesion in the upper lobe is associated with diagnostic failure. No difference was observed in the diagnostic yield based on the severity of airflow limitation. The complication rates were acceptable.