[Factors Associated with Diagnostic Yield of Endobronchial Ultrasonography with a Guide Sheath for Peripheral Lung Cancer]

Endobronchial Ultrasonography With Guide Sheath for the Diagnosis of Peripheral Pulmonary Lesions in Japan: A Literature Review

We evaluated the usefulness of endobronchial ultrasonography with guide sheath (EBUS-GS) for the diagnosis of peripheral pulmonary lesions (PPLs) in Japan. We searched the PubMed/Medline database using the keywords "EBUS guide sheath" for Japanese studies on EBUS-GS published between January 2004 and August 2023. We included 32 original articles that evaluated the diagnostic yield of EBUS-GS for PPLs. Case reports and conference abstracts were excluded due to limited information available for quality assessment. The diagnostic yield of EBUS-GS was 73.6% for 2996 malignant lesions, 65.4% for 752 ground-glass nodules, 59.4% for 414 benign lesions, 61.3% for 1114 lesions of size ≤2 cm, and 75.6% for 1246 lesions of size >2 cm; it was 69.4% for lesions located in the upper lobe (n=793), 71.9% for the middle lobe/lingula (n=121), and 62.5% for the lower lobe (n=334). None of the patients experienced severe complications. In this review, EBUS-GS is effective for the diagnosis of malignant and benign PPLs. A multimodality approach is needed to further enhance its diagnostic performance.

Improved diagnostic yield of transbronchial lung biopsy in peripheral pulmonary lesions using a combination of endobronchial ultrasound and rapid on-site evaluation

OBJECTIVES

To evaluate the value of rapid on-site evaluation (ROSE) during radial probe endobronchial ultrasound transbronchial lung biopsy (rpEBUS-TBLB) for peripheral pulmonary lesions (PPLs).

METHODS

One hundred and six patients with PPLs who received rpEBUS-TBLB were enrolled in this study. One specimen was immediately examined by ROSE and the other was sent to the central laboratory for cytologic diagnosis. The results of ROSE were compared with those of pathological diagnosis.

RESULTS

The diagnostic accuracy, sensitivity, and specificity of ROSE during rpEBUS-TBLB for PPLs were 82.1%, 89.6%, and 77.1%, respectively. The procedure times and number of biopsies were less for procedures when ROSE was positive compared with those when ROSE was negative (procedure time: 20.5 ± 7.9 vs. 28.3 ± 7.6 minutes; number of biopsies: 1.6 ± 0.9 vs. 2.8 ± 0.6 times). No serious procedural complications were observed.

CONCLUSIONS

ROSE has value for diagnosing PPLs during rpEBUS. It can reduce procedure time, number of biopsies, and complications. ROSE combined with rpEBUS is an effective and safe method for the diagnosis of PPLs.

Computed Tomography Bronchus Sign and the Diagnostic Yield of Guided Bronchoscopy for Peripheral Pulmonary Lesions. A Systematic Review and Meta-Analysis

RATIONALE

Indeterminate peripheral pulmonary lesions (PPLs) often require tissue diagnosis. If nonsurgical biopsy techniques are considered, deciding between bronchoscopic transbronchial versus computed tomography-guided transthoracic biopsy can be difficult. The former has a low diagnostic yield with a low complication risk, whereas the latter has a better diagnostic yield but a higher complication rate. Investigators have looked at various lesion characteristics that can predict the diagnostic yield of guided bronchoscopic biopsies. Although consensus exists that larger size and proximity to the hilum increase the diagnostic yield, there is ongoing debate about the association between computed tomography bronchus sign (air-filled bronchus in close proximity of the lesion as seen on computed tomography imaging) and the diagnostic yield of guided bronchoscopic modalities.

OBJECTIVES

To perform a meta-analysis and systematic review, determining the association between computed tomography bronchus sign and the diagnostic yield of guided bronchoscopy for PPLs.

METHODS

MEDLINE, Embase, Scopus, and Google Scholar were searched in January 2018 for guided bronchoscopy studies that had assessed the impact of computed tomography bronchus sign on the diagnostic yield. The quality of included studies was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 tool. Meta-analysis was performed using MedCalc (version 18). Odds ratios were used to compare yield of lesions with and without bronchus sign. Random effects model was used when significant heterogeneity was observed (I² > 40%).

RESULTS

For 2,199 lesions with computed tomography bronchus sign, the overall weighted diagnostic yield was 74.1% (95% confidence interval, 68.3-79.5%). For 971 lesions without computed tomography bronchus sign, the overall weighted diagnostic yield was 49.6% (95% confidence interval, 39.6-59.5%). The odds ratio for successfully diagnosing a lesion with computed tomography bronchus sign was 3.4 (95% confidence interval, 2.4-5.0). Possible sources of heterogeneity in the meta-analysis included differences in study designs, guidance modalities, and cancer prevalence. The odds ratio for successfully diagnosing a lesion with computed tomography bronchus sign was relatively lower for prospective studies.

CONCLUSIONS

PPLs with computed tomography bronchus sign are more likely to be diagnosed with guided bronchoscopy than the lesions without computed tomography bronchus sign. Clinicians should consider this, along with the lesion size and distance from the hilum, when contemplating guided bronchoscopy for PPLs.

A novel biosimulator based on ex vivo porcine lungs for training in peripheral tissue sampling using endobronchial ultrasonography with a guide sheath

Background

Although radial probe endobronchial ultrasonography (EBUS) with a guide sheath (GS; EBUS-GS) is widely used for sampling peripheral pulmonary lesions (PPLs), a standard training model for EBUS-GS remains to be developed. The purpose of this study was to evaluate the feasibility of a novel pulmonary biosimulator for hands-on training in peripheral tissue sampling using EBUS-GS.

Methods

We established a novel biosimulator for EBUS-GS using porcine lungs. The simulator was equipped with multiple pseudo PPLs that were created using blue agar solution injected through GS inserted in a bronchoscope. A total of 12 voluntary trainees participated in a hands-on training course using the biosimulator. The size of samples acquired using biopsy forceps were compared between initial and post-training biopsies, and trainee satisfaction with the biosimulator and training program were evaluated using a questionnaire.

Results

Under the guidance of a trainer, all trainees successfully detected pseudo PPLs using radial probe EBUS before the initial biopsy, and 11 trainees acquired samples from the target lesions during the initial biopsy. Post-training biopsy samples were larger than the initial samples for eight trainees. The results of the questionnaire revealed that all trainees were satisfied with the biosimulator. Moreover, eight trainees who had previously participated in another hands-on EBUS-GS training program involving a synthetic phantom model showed greater satisfaction for the biosimulator.

Conclusions

A hands-on training program using the novel biosimulator assessed in this study could aid clinicians in improving their skills for EBUS-GS and acquiring larger peripheral tissue samples using biopsy forceps inserted through GS.

Endobronchial ultrasonography using a guide sheath technique for diagnosis of peripheral pulmonary lesions

Endobronchial ultrasonography using a guide sheath (EBUS-GS) is a novel method used for collecting peripheral pulmonary lesion (PPL) samples. EBUS-GS is performed by introducing a guide sheath-covered miniprobe into the target bronchus and then withdrawing the miniprobe after lesion detection, leaving the guide sheath in situ as a working channel for obtaining lesion samples. EBUS-GS can improve PPL diagnosis rates and be used for obtaining specimens for molecular analysis. In this review, we discuss the clinical applications of EBUS-GS, the factors that affect its diagnostic sensitivity, and potential complications. We also compare EBUS-GS with other available diagnostic techniques and discuss the strengths and limitations of this method.