Radial endobronchial ultrasound in diagnosing peripheral lung lesions in a high tuberculosis setting

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

PURPOSE

Radial probe endobronchial ultrasound (RP-EBUS) accurately locates peripheral lung lesions (PLLs) during transbronchial biopsy (TBB). We performed an updated meta-analysis of the diagnostic yield of TBB for PLLs using RP-EBUS to generate recommendations for the development of the Korean Association of Lung Cancer guidelines.

MATERIALS AND METHODS

We systematically searched MEDLINE and EMBASE (from January 2013 to December 2022), and performed a meta-analysis using R software. The diagnostic yield was evaluated by dividing the number of successful diagnoses by the total lesion number. Subgroup analysis was performed to identify related factors.

RESULTS

Forty-one studies with a total of 13,133 PLLs were included. The pooled diagnostic yield of RP-EBUS was 0.72 (95% confidence interval [CI], 0.70 to 0.75). Significant heterogeneity was observed among studies (χ2=292.38, p < 0.01, I2=86.4%). In a subgroup analysis, there was a significant difference in diagnostic yield based on RP-EBUS findings (within, adjacent to, invisible), with a risk ratio of 1.45 (95% CI, 1.23 to 1.72) between within and adjacent to, 4.20 (95% CI, 1.89 to 9.32) between within and invisible, and 2.59 (95% CI, 1.32 to 5.01) between adjacent to and invisible. There was a significant difference in diagnostic yield based on lesion size, histologic diagnosis, computed tomography (CT) bronchus sign, lesion character, and location from the hilum. The overall complication rate of TBB with RP-EBUS was 6.8% (bleeding, 4.5%; pneumothorax, 1.4%).

CONCLUSION

Our study showed that TBB with RP-EBUS is an accurate diagnostic tool for PLLs with good safety profiles, especially for PLLs with within orientation on RP-EBUS or positive CT bronchus sign.

Safety and risk factors for bleeding complications of radial probe endobronchial ultrasound-guided transbronchial biopsy

BACKGROUND

Radial probe endobronchial ultrasound (radial EBUS) is widely used to diagnose pulmonary lesions; however, the diagnostic value of radial EBUS-guided transbronchial biopsy (TBB) varies, and its complications (especially the risk of bleeding) are not properly understood.

OBJECTIVES

In this study, we evaluated the diagnostic performance and rate of complication of this procedure, and investigated the risk factors associated with the procedure-related bleeding events.

DESIGN

A retrospective cohort study.

METHODS

This was a retrospective study that included consecutive patients who underwent radial EBUS-guided TBB. Radial EBUS was performed under moderate sedation in inpatients or outpatients. The severity of bleeding was graded using the standardized definitions of bleeding.

RESULTS

Of 133 patients (median age, 69 years; men 57.1%) included, 41 were outpatients (30.8%). The diagnostic accuracy, sensitivity, and specificity for malignancy were 76.1% (89/117), 71.1% (69/97), and 100% (20/20), respectively. The diagnostic accuracy ranged from 66.9% to 79.0%, depending on the classification of undiagnosed cases as either false negatives or true negatives. Twenty-seven patients (20.3%) developed complications (pneumothorax, 3; pneumonia, 5; complicated pleural effusion, 2; bleeding event grade 2 or higher, 21). Of the 41 outpatients, two developed complications (pneumothorax without intervention, 1; grade 2 bleeding event, 1). Of the 21 patients (15.8%) with procedure-related bleeding events, 18 had grade 2, and three had grade 3 bleeding complications. In multivariate analysis, a large size of ⩾30 mm (adjusted odds ratio (OR), 5.09; p = 0.03) and central lesion (adjusted OR, 3.67; p = 0.03) were significantly associated with the risk of grade 2 or higher bleeding events.

CONCLUSION

Our results suggest that radial EBUS-guided TBB is an accurate and safe method for diagnosing pulmonary lesions. Clinically significant procedure-related bleeding was rare. The central location and larger size (⩾30 mm) of pulmonary lesions were risk factors for grade 2 or higher bleeding events.

Diagnosis of pulmonary sarcoidosis in tuberculosis endemic area-a narrative review

Background and Objective

Pulmonary sarcoidosis and tuberculosis (TB) are the most frequent tissue-confirmed granulomatous diseases. Due to its unknown etiology, pulmonary sarcoidosis is diagnosed by ruling out other granulomatous diseases and necessitating clinical, radiological, and pathological evidence. There are many factors that contribute to the diagnostic dilemma between these two diseases. Even though some aspects of both diseases, such as their pathological evidence and abnormal X-ray findings, are quite similar, the treatment options for each are entirely different. The standard treatment for sarcoidosis is immunosuppressive agents such as glucocorticoids, which can exacerbate TB. Consequently, the overlap between clinical and radiological features constitutes a significant challenge for many physicians in selecting the optimal treatment for each patient. Therefore, the exclusion of pulmonary TB is a mandatory step for the diagnosis of pulmonary sarcoidosis. This article reviews and summarizes basic science and clinical research on distinguishing these two disorders.

Methods

A systematic search of the MEDLINE and PubMed databases focusing on studies published within the last 35 years was conducted. The last search date is February 4, 2023. The authors used the following combinations of terms: tuberculosis, sarcoidosis, diagnosis, bronchoscopy, biomarkers, and radiography. All studies were reviewed, and 69 references from 1990 to 2023 were found to be relevant.

Key Content and Findings

Innovative laboratory tests are essential for distinguishing between pulmonary sarcoidosis and TB. The Xpert MTB/RIF assay diagnoses TB with 98% sensitivity and 89% specificity. Loop-mediated isothermal amplification (LAMP) and simultaneous amplification and testing method for Mycobacterium tuberculosis rRNA (SAT-TB) are also highly sensitive and specific for TB diagnosis. Several novel tests, such as the difference of immune complexes for the ESAT-6/SFP-10 antigen in vitro with dynamic light scattering (DLS), lung tissue-based molecular markers, and the blood transcriptome, are promising for differentiating TB from sarcoidosis.

Conclusions

Recent advancements in laboratory investigations, non-invasive procedures, and invasive procedures play an important role in the diagnosis of sarcoidosis in TB-endemic areas. However, further study is needed to evaluate the diagnostic performance of all tests in terms of their competency in distinguishing between TB and sarcoidosis.

Guided Bronchoscopy for the Evaluation of Pulmonary Lesions: An Updated Meta-analysis

BACKGROUND

Guided bronchoscopy is increasingly used to diagnose peripheral pulmonary lesions (PPLs). A meta-analysis published in 2012 demonstrated a pooled diagnostic yield of 70%; however, recent publications have documented yields as low as 40% and as high as 90%.

RESEARCH QUESTION

Has the diagnostic yield of guided bronchoscopy in patients with PPLs improved over the past decade?

STUDY DESIGN AND METHODS

A comprehensive search was performed of studies evaluating the diagnostic yield of differing bronchoscopic technologies used to reach PPLs. Study quality was assessed using the Quality assessment of diagnostic accuracy of studies (QUADAS-2) assessment tool. Number of lesions, type of technology used, overall diagnostic yield, and yield by size were extracted. Adverse events were recorded. Meta-analytic techniques were used to summarize findings across all studies.

RESULTS

A total of 16,389 lesions from 126 studies were included. There was no significant difference in diagnostic yield prior to 2012 (39 studies; 3,052 lesions; yield 70.5%) vs after 2012 (87 studies; 13,535 lesions; yield 69.2%) (P > .05). Additionally, there was no significant difference in yield when comparing different technologies. Studies with low risk of overall bias had a lower diagnostic yield than those with high risk of bias (66% vs 71%, respectively; P = .018). Lesion size > 2 cm, presence of bronchus sign, and reports with a high prevalence of malignancy in the study population were associated with significantly higher diagnostic yield. Significant (P < .0001) between-study heterogeneity was also noted.

INTERPRETATION

Despite the reported advances in bronchoscopic technology to diagnose PPLs, the diagnostic yield of guided bronchoscopy has not improved.

Endobronchial ultrasound guided transbronchial cryobiopsy versus forceps biopsy in peripheral lung lesions

INTRODUCTION

Radial probe endobronchial ultrasound (RP-EBUS) is a modern technique for diagnosis of peripheral lung lesions. It is assumed that the addition of transbronchial cryobiopsy (TBCB) could increase the diagnostic value for RP-EBUS.

OBJECTIVES

The main objectives were to evaluate the efficacy and safety of RP-EBUS-guided TBCB for diagnosis of peripheral lung lesions and comparing it with RP-EBUS-guided transbronchial forceps biopsy.

METHODS

Sixty patients with peripheral lung diseases were divided into two groups. Group I included 45 patients who were eligible for TBCB and they subjected to forceps transbronchial biopsy (forceps TBB) and TBCB guided by RP-EBUS. Fifteen patients who were not eligible for TBCB were included in group II and they were subjected to forceps TBB and/or cytology retrieval procedures guided by RP-EBUS.

RESULTS

In group I, forceps TBB had sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of; 67.5%, 100%, 100%, 18.8%, and 69.8%, respectively, while TBCB had sensitivity, specificity, PPV, NPV, and accuracy of 75%, 100%, 100%, 23.1%, and 76.7%, respectively. The sensitivity in group II was 80% and the overall results including both groups were sensitivity, specificity, PPV, NPV, and accuracy of 85.2%, 100%, 100%, 42.8%, and 86.7%, respectively. Regarding the complications, only one patient (1.7%) had significant bleeding. One patient (1.7%) had pneumothorax and another patient (1.7%) suffered from hypoxemia.

CONCLUSIONS

RP-EBUS-guided TBCB is a safe and effective technique for diagnosis of peripheral lung lesions. TBCB has achieved higher diagnostic values and better quality of samples.

Adenocarcinoma of the Lung Mimicking Miliary Tuberculosis

Miliary shadows on chest imaging have wide differential diagnoses. The most common etiology is infectious, such as miliary tuberculosis (TB) and histoplasmosis, but miliary shadows can be the presentation of sarcoidosis, pneumoconiosis, and secondary metastasis to the lungs from primary cancers of the thyroid, kidney, and trophoblasts as well as sarcomas. Here we present the case of a 35-year-old Indian male who presented with a 2-month history of dry cough and shortness of breath. Chest imaging showed diffuse bilateral miliary nodules. The initial impression was that of miliary pulmonary TB. Subsequent bronchoscopy with a transbronchial biopsy confirmed the diagnosis of pulmonary mucinous adenocarcinoma with brain metastasis, which is a rare and unusual presentation of primary lung cancer. The tumor was positive for ALK5A4 and PD-L1, and the patient was started on tyrosine kinase inhibitor immunotherapy, with a favorable response.

Sensitivity of Radial Endobronchial Ultrasound-Guided Bronchoscopy for Lung Cancer in Patients With Peripheral Pulmonary Lesions: An Updated Meta-analysis

BACKGROUND

Registry trials have found radial endobronchial ultrasound (r-EBUS) sensitivity to vary between institutions, suggesting that in clinical practice, r-EBUS sensitivity may be lower than reported in clinical trials. We performed a meta-analysis to update the estimates of r-EBUS sensitivity and to explore factors contributing to heterogeneity of results.

METHODS

A systematic review using PubMed was performed through July 2018 to determine the sensitivity of r-EBUS for lung cancer, and to construct a summary receiver operating characteristic curve. The DerSimonian and Laird method was used to weight results. Subgroup analysis and meta-regression was used to identify sources of heterogeneity. Study quality was assessed using the QUADAS tool, and publication bias was tested using funnel plots.

RESULTS

Fifty-one studies with a total of 7,601 patients were included. r-EBUS pooled sensitivity was 0.72 (95% CI, 0.70-0.75), and area under the sROC curve was 0.96 (95% CI, 0.94-0.97). Significant heterogeneity was observed (I² = 76%; heterogeneity P < .01). We failed to demonstrate an association between sensitivity and air bronchus sign, average nodule size, use of fluoroscopy, virtual bronchoscopy, guide sheath, cancer prevalence, multicenter status, or consecutive enrollment. Rapid onsite cytology was associated with increased sensitivity (P = .01). The pooled pneumothorax rate was 0.7% (95% CI, 0.3%-1.1%). Funnel plots were asymmetrical, demonstrating sample size-related effects and possible publication bias.

CONCLUSIONS

r-EBUS has an excellent safety profile, but there is significant between-study heterogeneity. Sample size-related effects and possibly publication bias have led to overly optimistic estimates of the sensitivity of r-EBUS.

Performance of transbronchial cryobiopsy in eccentrically and adjacently orientated radial endobronchial ultrasound lesions

Background

Radial endobronchial ultrasound (R-EBUS) is an effective technique in the diagnosis of peripheral pulmonary lesions (PPL). However, lesion orientation with regards to the radial probe remains an important factor for effective biopsy. "Within" orientation was associated with significantly higher diagnostic yield. Cryobiopsy is a novel technique in obtaining larger tissue samples with the frozen tip allowing biopsy in a 360° direction, thus potentially achieving more effective biopsy in eccentrically and adjacently orientated lesions. We aimed to evaluate the performance and safety of transbronchial cryobiopsy versus forceps biopsy in eccentrically and adjacently orientated R-EBUS lesions.

Methods

Retrospective review of R-EBUS transbronchial biopsy for PPL over 17 months.

Results

114 R-EBUS scans were included for analysis during the study period. Forceps biopsy was performed in 76 (66.7%) cases and cryobiopsy in 38 (33.3%) cases. Baseline demographics and lesion characteristics did not differ between the two groups. Median (interquartile range) lesion size was 3.48 (2.63-4.51) cm. Overall, 41.2% of lesions were of eccentric orientation and 15.8% adjacent orientation; only 43% were concentric in orientation. Overall diagnostic yield was 67.5% (77 out of 114). Orientation remained an important factor affecting diagnostic yield. Transbronchial cryobiopsy significantly increased the diagnostic yield in eccentrically and adjacently orientated lesions to 75.0% (18 out of 24), compared to 48.8% (20 out of 41) obtained via forceps biopsy (p<0.05); but not in concentric lesions. Cryobiopsy was associated with more mild and moderate bleeding complications compared to the forceps biopsy group.

Conclusions

Transbronchial cryobiopsy under R-EBUS guidance is a safe procedure which potentially increases diagnostic yield in eccentrically and adjacently orientated PPLs.

Diagnostic Performance of Radial Probe Endobronchial Ultrasound without a Guide-Sheath and the Feasibility of Molecular Analysis

BACKGROUND

Radial probe endobronchial ultrasound (R-EBUS), is effective for tissue diagnosis of lung lesions. We evaluated the diagnostic performance of R-EBUS both a guide-sheath and fluoroscopy and identified factors associated with accurate diagnosis. The feasibility of molecular and genetic testing, using specimens obtained by R-EBUS, was also investigated.

METHODS

The study retrospectively reviewed 211 patients undergoing R-EBUS without a guide-sheath and fluoroscopy, June 2016-May 2017. After excluding 27 patients of which the target lesion was not reached, 184 were finally included. Multivariate logistic regression was used, to identify factors associated with accurate diagnosis.

RESULTS

Among 184 patients, R-EBUS-guided biopsy diagnosed malignancy in 109 patients (59%). The remaining 75 patients (41%) with non-malignant results underwent additional work-ups, and 34 were diagnosed with malignancy. Based on final diagnosis, diagnostic accuracy was 80% (136/170), and sensitivity and specificity for malignancy were 76% (109/143) and 100% (27/27), respectively. In multivariate analysis, peripheral location (adjusted odds ratio [aOR], 3.925; 95% confidence interval [CI], 1.203-12.811; p=0.023), and central position of the probe (aOR, 2.435; 95% CI, 1.424-7.013; p=0.035), were associated with accurate diagnosis of malignancy. Molecular and genetic analyses were successful, in all but one case, with inadequate specimens.

CONCLUSION

R-EBUS-guided biopsy without equipment, is effective for tissue diagnosis. Peripheral location and central position of the radial probe, were crucial for accurate diagnosis. Performance of molecular and genetic testing, using samples obtained by R-EBUS, was satisfactory.

Bronchoscopic techniques in the management of patients with tuberculosis

Tuberculosis (TB) is one of the leading causes of morbidity and mortality worldwide. Early diagnosis and treatment are key to prevent Mycobacterium tuberculosis transmission. Bronchoscopy can play a primary role in pulmonary TB diagnosis, particularly for suspected patients with scarce sputum or sputum smear negativity, and with endobronchial disease. Bronchoscopic needle aspiration techniques are accurate and safe means adopted to investigate hilar and mediastinal lymph nodes in cases of suspected TB lymphadenopathy. Tracheobronchial stenosis represents the worst complication of endobronchial tuberculosis. Bronchoscopic procedures are less invasive therapeutic strategies than conventional surgery to be adopted in the management of TB-related stenosis. We conducted a non-systematic review aimed at describing the scientific literature on the role of bronchoscopic techniques in the diagnosis and therapy of patients with TB. We focused on three main areas of interventions: bronchoscopic diagnosis of smear negative/sputum scarce TB patients, endobronchial TB diagnosis and treatment and needle aspiration techniques for intrathoracic TB lymphadenopathy. We described experiences on bronchoalveolar lavage, bronchial washing, and biopsy techniques for the diagnosis of patients with tracheobronchial and pulmonary TB; furthermore, we described the role played by conventional and ultrasound-guided transbronchial needle aspiration in the diagnosis of suspected hilar and mediastinal TB adenopathy. Finally, we assessed the role of the bronchoscopic therapy in the treatment of endobronchial TB and its complications, focusing on dilation techniques (such as balloon dilation and airway stenting) and ablative procedures (both heat and cold therapies).

Value of radial probe endobronchial ultrasound-guided transbronchial biopsy and computer tomography-guided transthoracic needle aspiration in the diagnosis of peripheral pulmonary lesions

Computer tomography-guided transthoracic needle aspiration (CT-TTNA) is a minimally invasive technique for sampling peripheral lung lesions. Radial endobronchial ultrasound-guided transbronchial biopsy (rEBUS-TBB) is an alternative. The present study analyzed and compared rEBUS-TBB and CT-TTNA in the diagnosis of peripheral pulmonary lesions (PPL).Clinical data of 513 patients with PPL who underwent an rEBUS-TBB or CT-TTNA examination were analyzed retrospectively. The positive diagnostic rate, complication rate, and influencing factors of the 2 methods were compared.The positive diagnostic rate and complication rate were significantly higher in CT-TTNA than rEBUS-TBB (P = .001; P < .001, respectively). The rEBUS-TBB group showed a higher positive diagnostic rate in larger lesions (>2 cm) than in smaller (≤2 cm) (P = .012), and was lower in the lesions proximal to the chest wall than those distally located (P = .046); no significant difference was observed in the different pulmonary segments (P = .109). In the CT-TTNA group, the positive diagnostic rate in larger lesions did not differ significantly than the smaller lesions (P = .05); it differed significantly in different segments (P = .044). The incidence of pneumothorax was lower in lesions proximal to the chest wall than those located distally (P = .037). In the rEBUS-TBB group, the success rate of the exploration and biopsy of the lesions was 87.4%; the rate of exploration of larger lesions and with bronchial sign was higher than smaller lesions and without bronchial sign (P < .001; P < .001, respectively) while that of lesions close to the chest wall was lower than those distally located (P = .006).rEBUS-TBB and CT-TTNA are effective and safe in the diagnosis of PPL. The positive diagnostic rate of CT-TTNA is higher than rEBUS-TBB. The incidence of pneumothorax in CT-TTNA is higher than rEBUS-TBB. CT-TTNA is selected for smaller lesions close to the chest wall; rEBUS-TBB is used for lesions larger, distal from the chest wall or with a bronchial sign.

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.

Radial endobronchial ultrasound with a guide sheath for diagnosis of peripheral cavitary lung lesions: a retrospective study

Background

Radial endobronchial ultrasound with a guide sheath (EBUS-GS) has improved the diagnostic outcomes of peripheral lung lesions. However, to our knowledge, reports on the use of EBUS-GS for diagnosis of cavitary lesions are unavailable. Therefore, this study aimed to assess the effectiveness and safety of EBUS-GS for diagnosis of peripheral cavitary lung lesions (PCLLs).

Methods

This study was a single-institution retrospective review of PCLLs examined by using EBUS-GS between July 2013 and October 2015. The diagnostic results of different EBUS-GS samples, including cytologic, histopathologic, and microbiologic samples, were analysed separately.

Results

Of 696 radial EBUS procedures performed during the study period, 50 were performed for examination of PCLLs. The overall diagnostic yield for EBUS-GS was 80 % (40/50). Regarding 27 malignant lesions, the diagnostic yields for cytologic and histopathologic samples were 63.0 % (17/27) and 74.1 % (20/27), respectively. Regarding 23 benign lesions, the diagnostic yields for histopathologic and microbiologic samples were 69.6 % (16/23) and 47.8 % (11/23), respectively. Uni- and multivariate analyses indicated that the EBUS probe being within the lesion was the only factor significantly associated with increased diagnostic yield (odds ratio, 7.04; P = 0.03). Although pulmonary infection occurred after the procedure in 1 patient (2.0 %), no other complications, including pneumothorax or significant haemorrhage, were reported.

Conclusion

EBUS-GS was found to be an effective and safe procedure for diagnosis of PCLLs.