Ultrathin Bronchoscopy with Multimodal Devices for Peripheral Pulmonary Lesions. A Randomized Trial

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.

Bronchoscopic navigation and tissue diagnosis

Diagnosis of early-stage lung cancer has become increasingly important as the detection of peripheral pulmonary lesions (PPLs) grows with widespread adoption of CT-based lung cancer screening. Although CT-guided transthoracic needle aspiration has been the standard diagnostic approach for PPLs, transbronchial sampling by bronchoscopy is often performed due to its reduced rate of adverse events. However, the diagnostic yield of conventional bronchoscopy is often poor. Various bronchoscopic technologies have emerged over recent years to address this limitation, including thin/ultrathin bronchoscopes, radial probe endobronchial ultrasound (RP-EBUS), virtual navigation bronchoscopy (VBN), electromagnetic navigation bronchoscopy (ENB), and robotic bronchoscopy. Bronchoscopic transparenchymal nodule access (BTPNA) and transbronchial access tool (TBAT) are novel techniques that leverage navigational bronchoscopic technologies to further improve access to lesions throughout the lung. The devices used for sampling tissue have similarly evolved, such as the introduction of cryobiopsy. These innovative bronchoscopic techniques allows higher diagnostic yield even in small PPLs. Given the complexity of these new techniques and technologies, it is important for physicians to understand their strengths and limitations.

A Prospective Randomized Comparative Study of Three Guided Bronchoscopic Approaches for Investigating Pulmonary Nodules: The PRECISION-1 Study

BACKGROUND

The capability of bronchoscopy in the diagnosis of peripheral pulmonary nodules (PPNs) remains limited. Despite decades of effort, evidence suggests that the diagnostic accuracy for electromagnetic navigational bronchoscopy (EMN) and radial endobronchial ultrasound (EBUS) approach only 50%. New developments in robotic bronchoscopy (RB) may offer improvements in the assessment of PPNs.

METHODS

A prospective single-blinded randomized controlled comparative study to assess success in localization and puncture of PPNs, using an ultrathin bronchoscope with radial EBUS (UTB-rEBUS) vs EMN vs RB in a human cadaver model of PPNs < 2 cm, was performed. The primary end point was the ability to successfully localize and puncture the target nodule, verified by cone-beam CT comparing RB and EMN. Secondary end points included needle to target position "miss" distance, and UTB-rEBUS comparisons.

RESULTS

Sixty procedures were performed to target 20 PPNs over the study period. Implanted PPNs were distributed across all lobes, with 80% located within the lung periphery. The target PPN mean diameter was 16.5 ± 1.5 mm, with 50% noted to have a CT bronchus sign. The rate of successful PPN localization and puncture was superior when using RB, compared with EMN (80% vs 45%; P = .02). Among unsuccessful needle passes, the median needle to target "miss" distance was significantly different when comparing UTB-rEBUS, EMN, and RB (P = .0014).

CONCLUSIONS

In a cadaver model, use of RB significantly increased the ability to localize and successfully puncture small PPNs when compared with existing technologies. This study demonstrates the potential of RB to precisely reach, localize, and puncture small nodules in the periphery of the lung.

State of the Art: Interventional Pulmonology

Interventional pulmonology (IP) has evolved over the past decade from an obscure subspecialty in pulmonary medicine to a recognized discipline offering advanced consultative and procedural services to patients with thoracic malignancy, anatomic airway disease, and pleural disease. Innovative interventions are now also available for diseases not traditionally treated procedurally, such as asthma and emphysema. The IP field has established certification examinations and training standards for IP training programs in an effort to enhance training quality and ensure competency. Validating new technology and proving its cost-effectiveness and effect on patient outcomes present the biggest challenge to IP as the health-care environment marches toward value-based health care. High-quality research is now thriving in IP and promises to elevate its practice into patient-centric evidence-based care.

Endobronchial removal of the high-risk osseous foreign bodies with evaluation and planning by virtual navigation system

We report herein on two cases where high-risk osseous foreign bodies that incarcerated or penetrated the bronchial wall. The foreign bodies were unable to be removed via flexible bronchoscope (FB), with the foreign bodies close to the pulmonary artery and aortic artery. After preoperative evaluation and planning with the virtual bronchoscopic navigation (VBN) system, the airway foreign bodies were extracted effectively and safely using advanced therapeutic endoscopic technique by rigid bronchoscope (RB), thus avoiding the surgical thoracotomy.

Factors leading to failure to diagnose pulmonary malignant tumors using endobronchial ultrasound with guide sheath within the target lesion

Background

The diagnostic yield of peripheral pulmonary lesions has significantly increased with the use of radial endobronchial ultrasound with guide sheath within the lesion. Here, we retrospectively evaluated factors leading to misdiagnosis of pulmonary malignant tumors using endobronchial ultrasound with the guide sheath within the lesion.

Methods

We assessed the final histopathological diagnosis of biopsy samples taken from 130 patients with lung malignant tumors that underwent endobronchial ultrasound with guide sheath within the lesion.

Results

Among 130 patients, 8 (6%) showed no definite malignant findings in biopsy samples but the presence of malignant cells (primary lung cancer 7, diffuse large B cell lymphoma 1) was subsequently confirmed by histopathological study of specimens taken by computed tomography-guided needle biopsy or surgery. Of the eight cases with diagnostic failure, the size of the biopsy sample was insufficient in five due to technical difficulties during the diagnostic procedure, and the diagnosis of malignant tumor was difficult in five cases because of extensive scarring tissue or central necrosis.

Conclusions

The results of this study showed that technical difficulties and/or pathological heterogeneity of the tumor might lead to failure to diagnose lung malignant tumor in cases using endobronchial ultrasound with guide sheath within the lesion.

Probe-based optical fiberscopy for the direct observation of peripheral pulmonary lesions

BACKGROUND

Peripheral pulmonary lesions are rarely observed directly before transbronchial biopsy. This study aimed to characterize the differences between malignant and benign peripheral pulmonary lesions according to the findings of direct observation using probe-based optical fiberscopy.

METHODS

Thirty patients who underwent probe-based optical fiberscopy in combination with bronchoscopy using endobronchial ultrasonography with a guide sheath for the evaluation of peripheral pulmonary lesions were prospectively included in this study. The patients were divided into the malignant and benign groups according to their final diagnosis. The findings of probe-based optical fiberscopy in the two groups were compared.

RESULTS

The numbers of patients who were diagnosed using histological or bacteriological analyses via bronchoscopic sampling in the malignant and benign groups were 20/23 (87.0%) and 2/7 (28.6%), respectively. On probe-based optical fiberscopy, angiogenesis and vascular engorgement were observed only in the malignant group. The disappearance of subepithelial microvessel transparency and presence of bronchiolar stenosis were observed more frequently in the malignant group (78.3% and 60.9%) than in the benign group (28.6% and 28.6%), whereas increased mucus secretion was observed more frequently in the benign group (71.4%) than in the malignant group (8.7%).

CONCLUSIONS

These results suggest that the findings of direct observation using probe-based optical fiberscopy are useful for differentiating malignant from benign peripheral pulmonary lesions.

TRIAL REGISTRY

UMIN-CTR; UMIN000018796; URL: https://www.umin.ac.jp/ctr/index.htm.

Use of an Ultrathin vs Thin Bronchoscope for Peripheral Pulmonary Lesions: A Randomized Trial

BACKGROUND

When evaluating peripheral pulmonary lesions, a 3.0-mm ultrathin bronchoscope (UTB) with a 1.7-mm working channel is advantageous regarding good access to the peripheral airway, whereas a 4.0-mm thin bronchoscope provides a larger 2.0-mm working channel, which allows the use of various instruments including a guide sheath (GS), larger forceps, and an aspiration needle. This study compared multimodal bronchoscopy using a UTB and a thin bronchoscope with multiple sampling methods for the diagnosis of peripheral pulmonary lesions.

METHODS

Patients with peripheral pulmonary lesions ≤ 30 mm in diameter were recruited and randomized to undergo endobronchial ultrasonography, virtual bronchoscopy, and fluoroscopy-guided bronchoscopy using a 3.0-mm UTB (UTB group) or a 4.0-mm thin bronchoscope (thin bronchoscope group). In the thin bronchoscope group, the use of small forceps with a GS or standard forceps without the GS was permitted. In addition, needle aspiration was performed for lesions into which an ultrasound probe could not be inserted.

RESULTS

A total of 360 patients were enrolled, and 356 were included in the analyses (median largest lesional diameter, 19 mm). The overall diagnostic yield was significantly higher in the UTB group than in the thin bronchoscope group (70.1% vs 58.7%, respectively; P = .027). The procedure duration was significantly shorter in the UTB group (median, 24.8 vs 26.8 min, respectively; P = .008). The complication rates were 2.8% and 4.5%, respectively (P = .574).

CONCLUSIONS

Multimodal bronchoscopy using a UTB afforded a higher diagnostic yield than that using a thin bronchoscope in the diagnosis of small peripheral pulmonary lesions.

TRIAL REGISTRY

UMIN Clinical Trials Registry; No.: UMIN000010133; URL: https://www.umin.ac.jp/ctr/.

Advances in interventional diagnostic bronchoscopy for peripheral pulmonary lesions

Introduction: The incidence of peripheral pulmonary lesions (PPLs) is growing following the adoption of lung cancer screening by low-dose chest CT. Although CT-guided transthoracic needle aspiration has been the standard method to diagnose PPLs, the field of interventional bronchoscopy is rapidly advancing to overcome complications of the transthoracic approach yet maintain the yield. Areas covered: This article reviews the clinical evidence of recent emerging interventional bronchoscopic techniques for diagnosis of PPLs. Expert opinion: Recent advances in interventional bronchoscopy contribute to not only the safety of transbronchial approaches to PPLs but also the higher diagnostic yield. To perform accurate sampling of PPLs, bronchoscopists must select the correct airway, approach the target as close as possible, and confirm the location of the target before sampling. These key steps can be assisted by recently developed technologies. However, it is important for bronchoscopists to understand the strengths and limitations of these emerging technologies.

Advances in Interventional Pulmonology

Much has changed since the last review of interventional pulmonology (IP) published in this Clinics series. The rate of development of new techniques and their complexities require IP physicians to be constantly maintaining and updating their skill set. International agreed training pathways help ensure that the interventionalists of the present and future have the required knowledge of anatomy, manual dexterity, and clinical judgment to keep up with the continuing advances that are constantly expanding IP's diagnostic and therapeutic boundaries. IP remains one of the most desirable subspecialities in pulmonology, and the technologic advances make the future an exciting one.

Diagnosing a solitary pulmonary nodule using multiple bronchoscopic guided technologies: A prospective randomized study

BACKGROUND

The rate of detection of pulmonary nodules on computed radiography (CR) is approximately 0.09-0.2%, so rapid identification of the nature of solitary pulmonary nodules (SPNs) with a likelihood of malignancy is a critical challenge in the early diagnosis of lung cancer.

OBJECTIVE

We conducted this study to compare the diagnostic yield and safety of endobronchial ultrasonography with a guide sheath (EBUS-GS), and the combination of EBUS-GS and virtual bronchoscopic navigation (VBN).

METHODS

This was a prospective, multicenter, multi-arm, randomized controlled trial involving a total of 1010 subjects. All the patients recruited underwent a chest CT scan which found SPNs that needed to be diagnosed. The subjects were randomly divided into one of three groups: a traditional, non-guided, bronchoscopy biopsy group (NGB group), an EBUS-GS guided bronchoscopy biopsy group (EBUS group), and a guided bronchoscopy biopsy group that combined EBUS-GS with VBN (combined group). The primary endpoint was to investigate the differences between the diagnostic yields of the three groups.

RESULTS

There was no significant difference in the diagnostic yield between the EBUS group (72.3%) and the combined group (74.3%), but the diagnostic yield for the NGB group was 41.2%. The time required to reach biopsy position was significantly less in the combined group (7.96 ± 1.18 min in the combined group versus 11.92 ± 5.37 min in the EBUS group, p < 0.05). However, the bronchoscope operation time was the same in the EBUS-GS and combined groups. The diagnostic yield for peripheral pulmonary lesions (PPLs) >20 mm in diameter was significantly higher than for those <20 mm in diameter.

CONCLUSION

The results of our study suggest that guided bronchoscopy could increase the diagnostic yield in the context of peripheral lesions. There was no significant difference in the diagnostic yield between the EBUS and combined groups, but use of EBUS-GS with VBN could significantly shorten the bronchoscope arrival time.

Diagnostic Yield of the Virtual Bronchoscopic Navigation System Guided Sampling of Peripheral Lung Lesions using Ultrathin Bronchoscope and Protected Bronchial Brush

OBJECTIVES

The use of an ultrathin bronchoscope (UB) to diagnose peripheral pulmonary lesions is described. A virtual bronchoscopic navigation system was used to direct the ultrathin scope to the nodule. One of the constraints of this technique was the inability to confirm the target lesion position during biopsy by using a conventional linear endobronchial ultrasound probe, since the probe does not fit into a 1.2 mm working channel of this bronchoscope. The aim of the study was to review our institutional experience with the use of a UB for sampling peripheral pulmonary lesions using the transbronchial brush guided by virtual bronchoscopy. We describe a technique wherein we attempt to brush all the visible bronchial sub-segments once the bronchoscope has reached close to the nodule.

MATERIALS AND METHODS

In total, 52 patients underwent the procedure between 2010 and 2017. A multiplanar computed tomography (CT) scan of the chest was obtained and subsequently uploaded to the Lung Point Virtual bronchoscopy navigation software. The UB was parked close to the lesion. All visible airway branches were then brushed using a protected bronchial brush. The data were retrospectively abstracted from the electronic medical records using standardized forms.

RESULTS

A total of 52 lesions (40 solid, 8 part-solid, 3 cavitary, and 1 ground-glass) were sampled using a transbronchial brush (median, 2; range, 1-8). Twenty-four lesions were under 2 cm in size. The overall success rates were 67.3%. The average diameter of nodules was 2.7±1.01 cm; 65% lesions were in the outer-third of the lungs. The cancer-specific sensitivity was 72.5%. The presence of bronchus sign; location of the lesion; and the characteristics, size, and stage of cancer did not have any impact on the diagnostic yield.

CONCLUSION

Virtual bronchoscopy-guided ultrathin bronchoscopy with bronchial brushing is safe and has a diagnostic yield comparable to other described techniques for evaluating peripheral pulmonary nodules.

A retrospective study comparing the ultrathin versus conventional bronchoscope for performing radial endobronchial ultrasound in the evaluation of peripheral pulmonary lesions

Background:

Few studies have reported on the utility of ultrathin bronchoscopes (UTBs) for performing radial probe endobronchial ultrasound (EBUS). Herein, we describe our experience with UTB and conventional bronchoscope (CB) for performing radial EBUS.

Materials and Methods:

This was a retrospective study comparing the diagnostic yield of a prototype UTB (external diameter 3 mm, working channel diameter 1.7 mm) versus CBs (external diameter ≥4.9 mm) in performing radial EBUS for the evaluation of peripheral pulmonary lesions (PPLs). Fluoroscopic guidance was not available.

Results:

A total of 121 subjects (34, UTB; 87, CB; 69.4% males) with a mean (standard deviation [SD]) age of 55.2 (14.8) years underwent radial EBUS. The mean (SD) size of PPLs on computed tomography of the thorax was 22.2 (13.7) mm. The lesions were significantly smaller in the UTB group (16.4 vs 24.7 mm, P = 0.006). Eight lesions could be visualized within the lumen of the peripheral smaller bronchi with the UTB. The overall yield of radial EBUS was 52.9% and was similar in the two groups (UTB vs. CB, 55.9% vs. 51.7%; P = 0.7). The procedure time was significantly shorter in the UTB group. On multivariate logistic regression, the yield was similar in the two groups after adjusting for the size and location of the lesion and position of the radial probe in relation to the lesion.

Conclusion:

Despite smaller lesions, radial EBUS performed with the UTB was found to have similar efficacy to that performed with the CB. More lesions could be visualized endobronchially using the UTB making it an attractive alternative for performing radial EBUS.

Standard Bronchoscopy With Fluoroscopy vs Thin Bronchoscopy and Radial Endobronchial Ultrasound for Biopsy of Pulmonary Lesions: A Multicenter, Prospective, Randomized Trial

BACKGROUND

New technology has resulted in bronchoscopy being increasingly used for diagnosing pulmonary lesions. Reported yield from these procedures varies widely with few randomized clinical trials. This study compares the diagnostic yield of a thin bronchoscope and radial endobronchial ultrasound (R-EBUS) with standard bronchoscopy and fluoroscopy (SB-F) in lung lesions.

METHODS

Patients presenting for diagnostic bronchoscopic evaluation at five centers were randomized to undergo SB-F or R-EBUS with a thin bronchoscope (TB-EBUS). If SB-F was nondiagnostic, crossover to the TB-EBUS arm was allowed. Data on patient demographics, radiographic features, and final pathologic or radiographic follow-up were collected. Statistical comparisons were made by Fisher exact test, χ2 test, and Student t test. Bivariate and multivariate analyses were performed to determine predictors of diagnostic yield.

RESULTS

One hundred and ninety-seven patients were included in the final analyses. There was no difference in demographics, lesion size, or location between study arms. The average lesion size was 31.2 mm (SD, 10.8 mm). Bronchoscopy was diagnostic in 87 patients (44%). Although the diagnostic yield was higher in the TB-EBUS arm compared with the SB-F arm (49% vs 37%), this difference was not statistically significant (P = .11). Among those with nondiagnostic bronchoscopic findings in the standard arm, 87% (n = 46) crossed over to TB-EBUS, resulting in a diagnosis in seven additional patients (15% of 46).

CONCLUSIONS

Bronchoscopy with or without a thin scope and R-EBUS had a poor diagnostic yield for pulmonary lesions. Future work should focus on improvements in technique and technology advances that ensure a higher likelihood of obtaining a diagnosis.

A review of existing and new methods of bronchoscopic diagnosis of lung cancer

Bronchoscopy is one of the main techniques used for sampling lung tumor biopsies. In recent years, a large number of tumor specimens have been required to determine the best chemotherapy regimen for each patient; this personalized approach is known as precision medicine. In this review, radial endobronchial ultrasound; bronchoscopic navigation systems, including virtual bronchoscopic navigation and electromagnetic navigation; ultrathin bronchoscope,; and endobronchial ultrasound-guided transbronchial needle aspiration are highlighted as techniques used to increase the diagnostic yield. Personalized therapy includes tests for analysis of epidermal growth factor mutations, anaplastic lymphoma kinase or ROS proto-oncogene 1 fusion gene, and programmed death ligand 1 expression. In cryobiopsy, a relatively large amount of tissue is collected from endobronchial lung cancer and peripheral pulmonary lesions, and it is a promising technique for analyzing these tissues using molecular tests.

Utility of a thin bronchoscope in facilitating bronchial thermoplasty

Background

A significant correlation has been previously demonstrated between the quantum of radiofrequency treatment delivered at bronchial thermoplasty and the degree of improvement in an asthmatic patient’s symptoms. The standard bronchoscope used for bronchial thermoplasty has an outer diameter of 4.8 mm at the distal tip. Thinner bronchoscopes are now available with the same internal channel size (2.0 mm). This study assesses whether using a thinner bronchoscope facilitates bronchial thermoplasty by increasing the radiofrequency activations delivered.

Patients and methods

This was a sequential study in a single center, conducted in 27 patients with very severe asthma. The first 12 patients (Group 1) underwent bronchial thermoplasty using the standard bronchoscope, Olympus BF-Q190. In the next group of eight patients (Group 2), the standard bronchoscope was used for all procedures except the left upper lobe, while the left upper lobe was treated with a smaller bronchoscope, Olympus BF-P190, with an outer diameter of 4.2 mm. In the last group of seven patients (Group 3), the smaller bronchoscope was used for every lobe. The quantum of radiofrequency treatment was measured by activations delivered to each lung lobe in each patient, and patient groups were compared by ANOVA.

Results

In this group of 27 patients, the mean age was 56.5±12.9 years, the mean Asthma Control Questionnaire-5 item version score was 3.2±1.0 and the mean FEV₁% predicted was 55.2±15.7. Bronchial thermoplasty treatment resulted in significant improvements in predicted Asthma Control Questionnaire-5 item version score (to 1.8±1.3, P<0.005), salbutamol rescue usage and oral corticosteroid requiring exacerbations, with no significant change in lung function. Use of the smaller bronchoscope resulted in greater radiofrequency treatment (total activations Group 1: 155±21, Group 2: 176±46, Group 3: 213±37; P<0.01). There were no significant differences in efficacy or safety outcomes among groups.

Conclusion

Using a thinner bronchoscope facilitates access to the bronchial tree and increases the radiofrequency treatment delivered at bronchial thermoplasty.

Diagnostic Value of Multi-Slice Spiral Computed Tomography for Bronchial Dysplasia in Premature Infants

Background

The aim of this study was to investigate the diagnostic value of multi-slice spiral computed tomography (MSCT) for bronchial dysplasia in premature infants.

Material/Methods

A retrospective analysis of 248 premature infants who were highly suspected to have bronchial dysplasia and were admitted to our hospital from 2015 onwards was conducted. We observed bronchus morphologies, sizes, and tissue characteristics using fiberoptic bronchoscopy (FB) as the criterion standard for diagnosis. We calculated the sensitivity, specificity, and diagnostic compliance of MSCT in the diagnosis of bronchial dysplasia.

Results

Thoracic computed tomography mainly revealed capsular bubbles. The translucency of the 2 lungs was reduced, and extensive and local ground-glass changes were observed. Imaging findings mostly included strip or honeycomb-like shadows. Pleural thickening and pleural effusion were rare. MSCT was able to establish a diagnosis in 92 cases (37.10%) of bronchopulmonary cysts, 69 cases (27.82%) of congenital pulmonary emphysema, 31 cases (12.50%) of bronchial atresia, 1 case (0.40%) of congenital cystadenoma malformation, and 3 cases (1.21%) of giant tracheal bronchitis. Another 52 children (20.97%) were found to have conventional pulmonary inflammation. The sensitivity of MSCT in the diagnosis of bronchial dysplasia was 88.21%, the specificity was 75.00%, and the diagnostic compliance was 86.29%. There was a significant difference between the MSCT and FB findings in the diagnosis of bronchial hypoplasia (P<0.001).

Conclusions

MSCT has great utility in the diagnosis of bronchial dysplasia in premature infants and may become an excellent method for diagnosing bronchial dysplasia in the future.

Atypical cells in pathology of endobronchial ultrasound-guided transbronchial biopsy of peripheral pulmonary lesions: incidence and clinical significance

BACKGROUND

Atypical cells may occasionally be the only pathologic finding in radial-probe endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) of peripheral pulmonary lesions (PPLs); however, it is uncertain how often we encounter such a situation and what clinical features can be used to identify these ambiguous PPLs, which are more likely to be malignant.

METHODS

From 2009 to 2016, consecutive patients referred for EBUS-guided TBB of PPLs and with pathology reports indicating atypical cells alone were included. Medical records were reviewed to extract patient demographics, clinical characteristics, procedural details and complications. The primary outcome was the final diagnosis of the PPLs on subsequent investigation. Multivariate logistic regression analysis was used to identify independent factors associated with a final malignant diagnosis.

RESULTS

One hundred sixty-five (7.2%) of 2291 patients had non-diagnostic TBB showing atypical cells. Benign and malignant diagnoses were subsequently obtained in 45 (27%) and 120 (73%) patients, respectively. The leading malignancy was lung adenocarcinoma; of note, a variety of benign lesions revealed cellular atypia on pathology, in particular, chronic inflammation, tuberculosis and pneumonia. Multivariate analysis indicated lesion appearance [solid vs. others; odds ratio (OR) 7.93; 95% confidence interval (CI) 2.94-21.40; P < 0.001] and probe position (adjacent to vs. within; OR 3.36; 95% CI 1.11-10.15; P = 0.032) were two significant factors predictive of a final diagnosis of malignancy.

CONCLUSIONS

One out of 14 EBUS-guided TBB procedures for PPLs exhibited atypical cells on pathology. Meticulous management strategies should be formulated to deal with these instances after taking into consideration lesion appearance, probe position and patient preferences.

Review of Recent Important Papers in Interventional Pulmonology

Interventional pulmonology is an innovative branch of pulmonary medicine that uses minimally invasive diagnostic and therapeutic approaches to airway, parenchymal, and pleural disease. The author reviews recent high-impact trials including randomized trials describing the use of endobronchial coils and valves in the management of severe emphysema. Novel approaches to the palliation of malignant and benign pleural effusion including increasing the frequency of drainage and instillation of talc via tunneled pleural catheters are also presented. In addition, a recent consensus paper discussing the optimal use and technique of cryobiopsy in diffuse parenchymal disease is reviewed, as well as a systematic review and meta-analysis of its diagnostic yield. The final trial reviewed in this article describes the preliminary safety and efficacy study of a novel endobronchial, balloon, and injection catheter for the local administration of chemotherapy into the airway mucosa so as to minimize the systemic absorption of these agents.

Electromagnetic navigation bronchoscopy under intravenous sedation-tips and tricks

Electromagnetic navigation bronchoscopy (ENB) is gaining acceptance and popularity amongst bronchoscopists as one of the tools to diagnose pulmonary nodules (PNs). Although the majority of ENBs in earlier studies were performed under general anaesthesia (GA), later reports suggest that the diagnostic yield of ENB under intravenous sedation (IVS) was comparable, and was time saving. ENB under IVS may potentially improve access of the techniques to practitioners and patients. However, it is technically challenging when compared to its performance under GA. This article reviews the techniques required for ENB under IVS to maximize its diagnostic yield and safety.

Usefulness of Bronchoscopic Rebiopsy of Non-Small Cell Lung Cancer with Acquired Resistance to Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor

Background: Approximately 50% of non-small cell lung cancer (NSCLC) patients with acquired resistance to EGFR-TKI harbor the EGFR mutation T790M. The recent development and wide use of third-generation EGFR-TKIs targeting T790M-mutant NSCLCs have increased the importance of rebiopsy after EGFR-TKI failure. We aimed to investigate the advantages of flexible bronchoscopy as a rebiopsy method and the prevalence of and factors affecting the T790M mutation after EGFR-TKI failure.

Methods: We investigated 139 patients who had undergone bronchoscopic rebiopsy and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) between Sep 2014 and Jul 2016.

Results: Among the 139 patients, bronchoscopic rebiopsy yielded successful pathological diagnoses in 102 (73.4%). Among them, 41 patients with EGFR-mutant lung adenocarcinoma and EGFR-TKI progression were selected for an investigation of T790M mutation prevalence at rebiopsy. The initial EGFR mutations were exon 19 del (56.1%), L858R or L861Q (34.1%), and others (9.8%). The most common rebiopsy method was transbronchial lung biopsy (41.5%), followed by EBUS-TBNA (26.8%) and endobronchial biopsy (19.5%). The median interval to T790M emergence was the longest among cases with exon 19 deletion (14.1 months), followed by exon 21 L858R or L861Q (11.3 months) and other rare EGFR mutations (2.9 months). The T790M mutation was identified in 18 (43.9%) patients, and exon 19 del was the most significant factor affecting T790M mutation development (hazard ratio: 6.875, P = 0.014).

Conclusions: Bronchoscopy was more useful than other rebiopsy approaches. The T790M emergence rate was highest in cases with exon 19 deletion, likely as a consequence of long-term EGFR-TKI exposure.

Interventional bronchoscopy in adults

INTRODUCTION

The field of interventional pulmonology (IP) is a rapidly maturing subspecialty of pulmonary medicine, which emphasizes advanced diagnostic and therapeutic bronchoscopy for the evaluation and management of central airway obstruction, mediastinal/hilar adenopathy and lung nodules/masses, as well as minimally invasive diagnostic and therapeutic pleural procedures. Areas covered: This review describes advances in diagnostic and therapeutic bronchoscopic techniques. Expert commentary: In the past decade, there has been a remarkable growth in available technology and equipment, as well as clinical and translational research efforts focused on patient-centered outcomes. Furthermore, the recent establishment of a uniform accreditation standard for all IP fellowship programs in the United States was an important step in the continued evolution of this subspecialty of pulmonary medicine.

Diagnosis of small pulmonary lesions by transbronchial lung biopsy with radial endobronchial ultrasound and virtual bronchoscopic navigation versus CT-guided transthoracic needle biopsy: A systematic review and meta-analysis

Background

Advances in bronchoscopy and CT-guided lung biopsy have improved the evaluation of small pulmonary lesions (PLs), leading to an increase in preoperative histological diagnosis.

We aimed to evaluate the efficacy and safety of transbronchial lung biopsy using radial endobronchial ultrasound and virtual bronchoscopic navigation (TBLB-rEBUS&VBN) and CT-guided transthoracic needle biopsy (CT-TNB) for tissue diagnosis of small PLs.

Methods

A systematic search was performed in five electronic databases, including MEDLINE, EMBASE, Cochrane Library Central Register of Controlled Trials, Web of Science, and Scopus, for relevant studies in May 2016; the selected articles were assessed using meta-analysis. The articles were limited to those published after 2000 that studied small PLs ≤ 3 cm in diameter.

Results

From 7345 records, 9 articles on the bronchoscopic (BR) approach and 15 articles on the percutaneous (PC) approach were selected. The pooled diagnostic yield was 75% (95% confidence interval [CI], 69–80) using the BR approach and 93% (95% CI, 90–96) using the PC approach. For PLs ≤ 2 cm, the PC approach (pooled diagnostic yield: 92%, 95% CI: 88–95) was superior to the BR approach (66%, 95% CI: 55–76). However, for PLs > 2 cm but ≤ 3 cm, the diagnostic yield using the BR approach was improved to 81% (95% CI, 75–85). Complications of pneumothorax and hemorrhage were rare with the BR approach but common with the PC approach.

Conclusions

CT-TNB was superior to TBLB-rEBUS&VBN for the evaluation of small PLs. However, for lesions greater than 2 cm, the BR approach may be considered considering its diagnostic yield of over 80% and the low risk of procedure-related complications.

A prospective study on the diagnosis of peripheral lung cancer using endobronchial ultrasonography with a guide sheath and computed tomography-guided transthoracic needle aspiration

Background:

It is difficult to collect peripheral lung cancer samples. This study analyzed the applicability of endobronchial ultrasonography with a guide sheath (EBUS-GS) and computed tomography-guided transthoracic needle aspiration (CT-TTNA) for the diagnosis of peripheral lung cancer.

Methods:

A prospective analysis of peripheral lung cancer patients was performed. The study included 150 cases in the EBUS-GS group and 177 cases in the CT-TTNA group. The diagnostic rate, pathological type, genetic status and complications were analyzed.

Results:

The diagnosis rates were 64.0% and 97.7% in the EBUS-GS and CT-TTNA groups, respectively. The EBUS-GS group had undergone the most operations of the upper lobes of both lungs, while there was no significant difference in the operation distribution among the lobes in the CT-TTNA group. Adenocarcinoma (64 cases versus 51 cases) was most commonly observed in both groups, followed by squamous cell carcinoma. The detection rates of patients who were given a genetic test were 96.1% and 98.9% in the EBUS-GS and CT-TTNA groups, respectively. The incidence of complications in the EBUS-GS group was significantly less than that in the CT-TTNA group.

Conclusions:

EBUS-GS and CT-TTNA both had operational limitations. The diagnostic rate of EBUS-GS was lower than that of CT-TTNA, but there were fewer complications. CT-TTNA had better tolerance. According to the specific location of the lesion, we recommend EBUS-GS for lesions with a diameter ⩽30 mm and CT-TTNA for lesions with a diameter >30 mm. CT-TTNA specimens were advantageous for genetic testing.

State-of-the-Art Modalities for Peripheral Lung Nodule Biopsy

Lung nodules are being increasingly detected, particularly with lung cancer screening with low-dose computed tomography. Although the vast majority of lung nodules are benign, many often require tissue diagnosis. Several modalities to obtain diagnostic tissue from peripheral lung nodules are available. Bronchoscopic modalities such as radial ultrasound and electromagnetic navigational bronchoscopy are becoming increasingly used because of their superior safety profile and improving diagnostic yield. Although these modalities continue to become more advanced, newer and complementary technologies appear promising.

Napsin A levels in epithelial lining fluid as a diagnostic biomarker of primary lung adenocarcinoma

BACKGROUND

It is crucial to develop novel diagnostic approaches for determining if peripheral lung nodules are malignant, as such nodules are frequently detected due to the increased use of chest computed tomography scans. To this end, we evaluated levels of napsin A in epithelial lining fluid (ELF), since napsin A has been reported to be an immunohistochemical biomarker for histological diagnosis of primary lung adenocarcinoma.

METHODS

In consecutive patients with indeterminate peripheral lung nodules, ELF samples were obtained using a bronchoscopic microsampling (BMS) technique. The levels of napsin A and carcinoembryonic antigen (CEA) in ELF at the nodule site were compared with those at the contralateral site. A final diagnosis of primary lung adenocarcinoma was established by surgical resection.

RESULTS

We performed BMS in 43 consecutive patients. Among patients with primary lung adenocarcinoma, the napsin A levels in ELF at the nodule site were markedly higher than those at the contralateral site, while there were no significant differences in CEA levels. Furthermore, in 18 patients who were undiagnosed by bronchoscopy and finally diagnosed by surgery, the napsin A levels in ELF at the nodule site were identically significantly higher than those at the contralateral site. In patients with non-adenocarcinoma, there were no differences in napsin A levels in ELF. The area under the receiver operator characteristic curve for identifying primary lung adenocarcinoma was 0.840 for napsin A and 0.542 for CEA.

CONCLUSION

Evaluation of napsin A levels in ELF may be useful for distinguishing primary lung adenocarcinoma.

Virtual bronchoscopic navigation without X-ray fluoroscopy to diagnose peripheral pulmonary lesions: a randomized trial

Background

Transbronchial biopsy for peripheral pulmonary lesions is generally performed under X-ray fluoroscopy. Virtual bronchoscopic navigation (VBN) is a method in which virtual images of the bronchial route to the lesion are produced based on CT images obtained before VBN, and the bronchoscope is guided using these virtual images, improving the diagnostic yield of peripheral pulmonary lesions. VBN has the possibility of eliminating the need for X-ray fluoroscopy in the bronchoscopic diagnosis of peripheral lesions. To determine whether VBN can be a substitute for X-ray fluoroscopy, a randomized multicenter trial (non-inferiority trial) was performed in VBN and X-ray fluoroscopy (XRF) -assisted groups.

Methods

The non-inferiority margin in the VBN-assisted group compared with the XRF-assisted group was set at 15%. The subjects consisted of 140 patients with peripheral pulmonary lesions with a mean diameter > 3 cm. In the VBN-assisted group, the bronchoscope was guided to the lesion using a VBN system without X-ray fluoroscopy. In the XRF-assisted group, the same bronchoscope was guided to the lesion under X-ray fluoroscopy. Subsequently, in both groups, the lesion was visualized using endobronchial ultrasonography with a guide sheath (EBUS/GS), and biopsy was performed. In this serial procedure, X-ray fluoroscopy was not used in the VBNA group.

Results

The subjects of analysis consisted of 129 patients. The diagnostic yield was 76.9% (50/65) in the VBN-assisted group and 85.9% (55/64) in the XRF-assisted group. The difference in the diagnostic yield between the two groups was -9.0% (95% confidence interval: -22.3% ~ 4.3%). The non-inferiority of the VBN-assisted group could not be confirmed. The rate of visualizing lesions by EBUS was 95.4% (62/65) in the VBN-assisted group and 96.9% (62/64) in the XRF-assisted group, being high in both groups.

Conclusions

On EBUS/GS, a bronchoscope and biopsy instruments may be guided to the lesions using VBN without X-ray fluoroscopy, but X-ray fluoroscopy is necessary to improve the accuracy of sample collection from lesions. During transbronchial biopsy for peripheral pulmonary lesions, VBN cannot be a substitute for X-ray fluoroscopy.

Trial registration

UMIN-CTR (UMIN000001710); registered 16 February 2009.

The value of repeat radial-probe endobronchial ultrasound-guided transbronchial biopsy after initial non-diagnostic results in patients with peripheral pulmonary lesions

Background

Radial-probe endobronchial ultrasound (rEBUS)-guided transbronchial biopsy (TBB) is invaluable in the diagnosis of peripheral pulmonary lesions (PPLs); however, in certain instances, the procedure has to be repeated because of initial non-diagnostic procedure(s). Little if any literature has been published on this issue. Therefore, the aim of this study was to investigate the utility of repeat rEBUS-guided TBB in achieving a definitive diagnosis of PPLs.

Methods

All patients who underwent rEBUS-guided TBB of PPLs at National Taiwan University Hospital between 2011 and 2015 and had a repeat procedure after non-diagnostic initial procedures were identified as the study subjects. The primary outcome of interest was the diagnostic yield of repeat rEBUS-guided TBB for PPLs. Also, we sought to discover features associated with the yield of repeat procedures.

Results

Forty-three (11%) out of 384 patients with initial non-diagnostic TBB were included for analysis. A diagnosis of PPLs was able to be confirmed with repeat TBB in 23(53%) patients. The pathology of the first TBB was significantly associated with the yield of repeat procedures (P = 0.011). Further, patients with normal lung tissue in initial pathology rarely (2/12, 17%) had a definite diagnosis on repeat TBB. Yet, patients with pathology showing atypical cells and other non-specific findings were more likely (21/31, 68%) to obtain a confirmed diagnosis. The diagnostic yield of repeat procedures was not affected by the size, location or CT appearance of the lesions, or position of the rEBUS probe. No death or other serious adverse events occurred with the repeat rEBUS-guided procedures.

Conclusions

If clinically indicated, it is reasonable to repeat rEBUS-guided TBB after an initial non-diagnostic procedure as the diagnostic yield will be at least 50% and the side effect profile is favorable.

Bronchoscopy for the diagnosis of peripheral lung lesions

Peripheral pulmonary lesions (PPLs) are generally considered as lesions in the peripheral one-third of the lung although a precise definition and radiographic anatomical landmarks separating central and peripheral lesion does not yet exist. The radiographic detection of such lesions has increased significantly with the adoption of lung cancer screening programs. These lesions are not directly visible by regular flexible bronchoscopes as they are usually distal to the lobar and segmental bronchi. Traditionally, depending on location and clinical stage at presentation, these lesions were typically sampled by computerized tomography (CT) guided needle or surgical biopsy although some centers also used ultrasound and fluoroscopy guided percutaneous needle biopsy. Due to lack of direct visualization, the yield for bronchoscopic guided sampling especially of the small <2 cm pulmonary nodules was very low. Therefore, sampling has been preferentially performed by percutaneous CT guidance, which had high yield of above 90% but it comes at the cost of higher risk complications like pneumothorax with reported rate of 15% to 28%. Directly proceeding to surgical resection is also considered in appropriate candidates with high suspicion of malignancy without any evidence of distant metastasis but the proportion of such cases of lung cancer is low. The manuscript discussed the various bronchoscopic diagnostic modalities for peripheral pulmonary lesions. It is important to note that most of the studies in this field are relatively small, not randomized, suffer from selection bias, have considerable heterogeneity in sampling methodology/instruments and usually have been performed in high volume institutions by dedicated highly experienced proceduralists. The prevalence of malignancy in most of the reported cohorts has also been high which may result in higher diagnostic yields. All these factors need to be kept in mind before generalizing the results to individual centers and practices.

Experience improves the performance of endobronchial ultrasound-guided transbronchial biopsy for peripheral pulmonary lesions: A learning curve at a medical centre

Background

Endobronchial ultrasound(EBUS)-guided transbronchial biopsy(TBB) is the preferred diagnostic tool for peripheral pulmonary lesions(PPLs) and mastering this procedure is an important task in the training of chest physicians. Little has been published about the learning experience of physicians with this technique, particularly at an institutional level. We aimed to establish a learning curve for EBUS-guided TBB for PPLs at a medical center.

Methods

Between 2008 and 2015, consecutive patients with PPLs referred for EBUS-guided TBB at National Taiwan University Hospital were enrolled. To build the learning curve, the diagnostic yield of TBB (plus brushings and washings) was calculated and compared. Meanwhile, lesion characteristics, and procedure-related features and complications were obtained to analyze associations with TBB yield and safety profile.

Results

A total of 2144 patients were included and EBUS-guided TBB was diagnostic for 1547(72%). The TBB yield was 64% in 2008 and reached a plateau of 72% after 2010. It took approximately 400 EBUS-guided procedures to achieve stable proficiency. Further analysis showed that improvement in diagnostic yield over time was mainly observed in PPLs, in cases in which the diameter was ≤2 cm or the EBUS probe could not be positioned within. Complication rates were low, with 1.8% and 0.5% for pneumothorax and hemorrhage, respectively.

Conclusions

Even though EBUS-guided TBB is an easy-to-learn technique, it takes 3 years or around 400 procedures for a medical center to achieve a better and stable performance. In particular, the diagnostic yield for lesions without the probe within or those sized ≤2 cm could improve with time.

[Application of Interventional Bronchoscopy in Pulmonary Peripheral Lesions]

肺癌是全球癌症相关死亡的主要原因, 肺癌的治愈率很低, 不仅因其自身攻击性, 还因对肺癌筛查的忽视。随着肺部筛查手段的不断进展, 肺外周病变的检出率逐渐提高, 当前对外周肺病变进行诊断的最常用方法是经支气管行支气管镜检查或计算机断层扫描(computed tomography, CT)引导下经皮穿刺针吸/活检, 然而对于外周肺病灶, 支气管镜检查有较低的诊断率, 经皮穿刺检查有较高的气胸发生率, 因此, 使用安全、微创的方法对外周肺病变进行组织确诊是临床工作者将面临的挑战。新型支气管镜介入诊断技术已逐渐用于临床, 这些技术可有效提高外周肺病变的诊断率, 缩短诊断时间, 使患者获得及时有效的治疗。本文将现有的技术进行简要综述以帮助临床医生尝试应用这些微创技术。

Gaining access to the periphery of the lung: Bronchoscopic and transthoracic approaches

Globally, lung cancer remains the leading cause of cancer-related death. Annual low-dose computed tomography has been recommended as a screening test for early detection of lung cancers. Implementing this screening strategy is expected to challenge pulmonologist to confirm the nature of the increasing number of detected pulmonary nodules. Clinicians are obliged to use the less invasive and most efficient and safe means to set diagnoses. Hence, the field of diagnostic modalities, especially the advanced diagnostic bronchoscopy is witnessing rapid evolution to fulfill these unmet needs. This review highlights the available diagnostic modalities, describes their advantages and discusses the limitations of each technique. It also suggests an integrated diagnostic algorithm based on the best available evidence. A search of the PubMed database was conducted using relevant terms described at methodology; only articles in English were reviewed by November 2016.

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.

Predictive factors for a successful diagnostic bronchoscopy of ground-glass nodules

INTRODUCTION:

Since the National Lung Screening Trial demonstrated the utility of low-dose computed tomography screening for lung cancer, the detection rate of ground-glass nodules (GGNs) has increased. Endobronchial ultrasound with a guide sheath (EBUS-GS) is widely performed to diagnose peripheral pulmonary lesions, but there are not enough reports on the predictive ability of EBUS-GS in diagnosing GGNs. The aim of this study is to investigate the predictive factors for a successful diagnostic bronchoscopy for GGNs.

METHODS:

Consecutive patients who underwent diagnostic bronchoscopy for GGNs from September 2012 to January 2016 were enrolled in this study. From these, cases who underwent EBUS-GS were selected. They were reviewed and analyzed to examine the association between the diagnostic yield and the following clinical factors: lesion size, lobar position, location, consolidation-to-tumor ratio, visibility on X-ray, use of virtual bronchoscopy, bronchus sign, guide sheath size, and number of biopsies.

RESULTS:

We enrolled 254 cases, of which 167 were diagnosed using EBUS-GS (65.7% diagnostic yield). Univariate analysis indicated that a positive bronchus sign was a significant factor for higher diagnostic yield (72.9% vs. 34.0%; P < 0.001). The use of virtual bronchoscopy also tended toward a higher yield, but the result was not significant (69.0% vs. 54.4%; P = 0.058). However, multivariate analysis indicated that both were significantly associated with higher diagnostic yield (P < 0.001, odds ratio [OR]: 5.35; P < 0.001, OR: 1.97, respectively).

CONCLUSIONS:

Our results suggest that a positive bronchus sign and the use of virtual bronchoscopy are positive predictive factors for successful diagnostic bronchoscopy of GGNs.