The Impact of Alternative Approaches to Diagnostic Yield Calculation in Studies of Bronchoscopy

Diagnostic yield of cone beam CT based navigation bronchoscopy in patients with metastatic lesions: A propensity score matched case-control study

BACKGROUND

Cone beam CT based Navigation Bronchoscopy (CBCT-NB) has predominantly been investigated as a diagnostic tool in (suspected) primary lung cancers. Small metastatic lesions are clinically considered more challenging to diagnose, but no study has explored the yield of navigation bronchoscopy in patients with pulmonary metastatic lesions (ML) compared to primary lung cancers (PL), correcting for known lesion characteristics affecting diagnostic yield.

MATERIALS AND METHODS

This is a single-center, retrospective, propensity score-matched case-control study. We matched a subset of patients who underwent CBCT-NB and received a final diagnosis of pulmonary metastases of solid tumors between December 2017 and 2021 against confirmed primary lung cancer lesions subjected to CBCT-NB in the same time period. The lesions were propensity score matched based on known characteristics affecting yield, including location (upper lobe, lower lobe), size, bronchus sign, and lesion solidity.

RESULTS

Fifty-six metastatic pulmonary lesions (mean size 14.7 mm) were individually case-matched to a selection of 297 available primary lung cancer lesions. Case-matching revealed non-significant differences in navigation success rate (PL: 89.3 % vs. ML: 82.1 %, 95%CI on differences: -21.8 to +7.5) and yield (PL: 60.7 % vs. ML: 55.4 %, 95%CI on differences: -25.4 to +14.7). The overall complication rate was comparable (5.4 % in PL vs. 5,4 % in ML).

CONCLUSION

After matching primary and metastatic lesions based on CT assessable lesions characteristics, CBCT-NB showed no clinically relevant or significantly different navigation success or yield in either group. We recommend a careful assessment of CT characteristics to determine procedural difficulty rather than selecting based on the suspicion of lesion origin.

Imaging modalities during navigational bronchoscopy

INTRODUCTION

Lung nodules are commonly encountered in clinical practice. Technological advances in navigational bronchoscopy and imaging modalities have led to paradigm shift from nodule screening or follow-up to early lung cancer detection. This is due to improved nodule localization and biopsy confirmation with combined modalities of navigational platforms and imaging tools. To conduct this article, relevant literature was reviewed via PubMed from January 2014 until January 2024.

AREAS COVERED

This article highlights the literature on different imaging modalities combined with commonly used navigational platforms for diagnosis of peripheral lung nodules. Current limitations and future perspectives of imaging modalities will be discussed.

EXPERT OPINION

The development of navigational platforms improved localization of targets. However, published diagnostic yield remains lower compared to percutaneous-guided biopsy. The discordance between the actual location of lung nodule during the procedure and preprocedural CT chest is the main factor impacting accurate biopsies. The utilization of advanced imaging tools with navigation-based bronchoscopy has been shown to assist with localizing targets in real-time and improving biopsy success. However, it is important for interventional bronchoscopists to understand the strengths and limitations of these advanced imaging technologies.

Early comparison robotic bronchoscopy versus electromagnetic navigational bronchoscopy for biopsy of pulmonary nodules in a thoracic surgery practice

Pulmonary nodules are frequently encountered in high-risk patients. Often these require biopsy which can be challenging. We relate our experience comparing use of electromagnetic navigational bronchoscopy (ENB) to a robotic bronchoscopy system (RB). A retrospective review of patients undergoing bronchoscopic biopsy from 2015 to 2021. The timeframe overlapped with transition from ENB using Veran SPiN system to RB using Ion system by Intuitive. Patient and nodule characteristics were collected. Primary end point was overall diagnostic yield which was defined by pathologic confirmation of malignancy or benign finding. Secondary outcomes included diagnostic yield based on overall size of nodules and need for further work up and testing. 116 patients underwent ENB or RB of 134 nodules. No perioperative complications occurred. Diagnostic yield of ENB was 49.5% (41/91 nodules) versus 86.1% (37/43 nodules) for RB. Average nodule size for ENB was 2.55 cm versus 1.96 cm for RB. When divided based on size, ENB had a 30% diagnostic yield for nodules 1-2 cm (11/37 nodules, mean size 1.46 cm) and 64% yield for nodules 2-3 cm (14/22 nodules, mean size 2.38 cm). RB had an 81% yield for nodules 1-2 cm (mean size 1.41 cm) and 100% yield for nodules 2-3 cm (mean 2.3 cm). RB showed superiority over ENB in early implementation trials for biopsy of suspicious pulmonary nodules. It is a safe technology allowing for increased access to all lung fields and utilization in the thoracic surgical practice will be paramount to advancing the field.

Mobile cone-beam computed tomography complementing shape-sensing robotic-assisted bronchoscopy in the small pulmonary nodule sampling: A multicentre experience

BACKGROUND AND OBJECTIVE

Shape-sensing robotic-assisted bronchoscopy (ssRAB) has expanded as an important diagnostic tool for peripheral pulmonary nodules (PPNs), with diagnostic yields ranging from 60% to 88%. However, sampling and diagnosing PPN less than 2 cm in size has historically been challenging. Mobile cone-beam computed tomography (mCBCT) has been recently integrated into ssRAB to improve diagnostic accuracy, but its added value remains uncertain. We aim to describe the role of mCBCT and determine if it provides any diagnostic advantage.

METHODS

A multicentre, retrospective study on the use of ssRAB and mCBCT in two tertiary care institutions: Mayo Clinic Florida and Massachusetts General Hospital. The primary outcome was diagnostic yield and sensitivity for malignancy of ssRAB complemented with mCBCT, compared to ssRAB with the standard 2D fluoroscopy.

RESULTS

A total of 192 nodules were biopsied from 173 patients. mCBCT was used in 117 (60.9%) nodules. The overall diagnostic yield was 85.4%. Diagnostic yield between subgroups with and without mCBCT was 83.8% and 88% (p = 0.417), respectively. The mCBCT group had fewer solid nodules (65.8% vs. 81.3%, p = 0.020) and a higher number of ground-glass nodules (10.3% vs. 1.3%, p = 0.016).

CONCLUSION

Overall, diagnostic yield between subgroups with and without mCBCT was similar. The complementary use of mCBCT to ssRAB allows proceduralists to target more complex and subsolid PPNs with a diagnostic yield comparable to simple solid PPNs while maintaining an excellent safety profile.

Cone-beam CT-based Navigation With Augmented Fluoroscopy of the Airways for Image-guided Bronchoscopic Biopsy of Peripheral Pulmonary Nodules: A Prospective Clinical Study

BACKGROUND

Cone-beam computed tomography (CBCT) and augmented fluoroscopy (AF), in which intraprocedural CBCT data is fused with fluoroscopy, have been utilized as a novel image-guidance technique for biopsy of peripheral pulmonary lesions. The aim of this clinical study is to determine the safety and diagnostic performance of CBCT-guided bronchoscopy with advanced software tools for procedural planning and navigational guidance with AF of the airways for biopsy of peripheral pulmonary nodules.

METHODS

Fifty-two consecutive subjects were prospectively enrolled in the AIRWAZE study (December 2018 to October 2019). Image-guided bronchoscopic biopsy procedures were performed under general anesthesia with specific ventilation protocols in a hybrid operating room equipped with a ceiling-mounted C-arm system. Procedural planning and image-guided bronchoscopy with CBCT and AF were performed using the Airwaze investigational device.

RESULTS

A total of 58 pulmonary lesions with a median size of 19.0 mm (range 7 to 48 mm) were biopsied. The overall diagnostic yield at index procedure was 87.9% (95% CI: 77.1%-94.0%). No severe adverse events related to CBCT-guided bronchoscopy, such as pneumothorax, bleeding, or respiratory failure, were observed.

CONCLUSION

CBCT-guided bronchoscopic biopsy with augmented fluoroscopic views of the airways and target lesion for navigational guidance is technically feasible and safe. Three-dimensional image-guided navigation biopsy is associated with high navigational success and a high diagnostic yield for peripheral pulmonary nodules.

Cone-beam CT imaging for robotic navigation bronchoscopy

See related article

Assessment of Advanced Diagnostic Bronchoscopy Outcomes for Peripheral Lung Lesions: A Delphi Consensus Definition of Diagnostic Yield and Recommendations for Patient-centered Study Designs. An Official American Thoracic Society/American College of Chest Physicians Research Statement

Background: Advanced diagnostic bronchoscopy targeting the lung periphery has developed at an accelerated pace over the last two decades, whereas evidence to support introduction of innovative technologies has been variable and deficient. A major gap relates to variable reporting of diagnostic yield, in addition to limited comparative studies. Objectives: To develop a research framework to standardize the evaluation of advanced diagnostic bronchoscopy techniques for peripheral lung lesions. Specifically, we aimed for consensus on a robust definition of diagnostic yield, and we propose potential study designs at various stages of technology development. Methods: Panel members were selected for their diverse expertise. Workgroup meetings were conducted in virtual or hybrid format. The cochairs subsequently developed summary statements, with voting proceeding according to a modified Delphi process. The statement was cosponsored by the American Thoracic Society and the American College of Chest Physicians. Results: Consensus was reached on 15 statements on the definition of diagnostic outcomes and study designs. A strict definition of diagnostic yield should be used, and studies should be reported according to the STARD (Standards for Reporting Diagnostic Accuracy Studies) guidelines. Clinical or radiographic follow-up may be incorporated into the reference standard definition but should not be used to calculate diagnostic yield from the procedural encounter. Methodologically robust comparative studies, with incorporation of patient-reported outcomes, are needed to adequately assess and validate minimally invasive diagnostic technologies targeting the lung periphery. Conclusions: This American Thoracic Society/American College of Chest Physicians statement aims to provide a research framework that allows greater standardization of device validation efforts through clearly defined diagnostic outcomes and robust study designs. High-quality studies, both industry and publicly funded, can support subsequent health economic analyses and guide implementation decisions in various healthcare settings.

Shape-Sensing Robotic-Assisted Bronchoscopy versus Computed Tomography-Guided Transthoracic Biopsy for the Evaluation of Subsolid Pulmonary Nodules

INTRODUCTION

Lung cancer remains the leading cause of cancer death worldwide. Subsolid nodules (SSN), including ground-glass nodules (GGNs) and part-solid nodules (PSNs), are slow-growing but have a higher risk for malignancy. Therefore, timely diagnosis is imperative. Shape-sensing robotic-assisted bronchoscopy (ssRAB) has emerged as reliable diagnostic procedure, but data on SSN and how ssRAB compares to other diagnostic interventions such as CT-guided transthoracic biopsy (CTTB) are scarce. In this study, we compared diagnostic yield of ssRAB versus CTTB for evaluating SSN.

METHODS

A retrospective study of consecutive patients who underwent either ssRAB or CTTB for evaluating GGN and PSN with a solid component less than 6 mm from February 2020 to April 2023 at Mayo Clinic Florida and Rochester. Clinicodemographic information, nodule characteristics, diagnostic yield, and complications were compared between ssRAB and CTTB.

RESULTS

A total of 66 nodules from 65 patients were evaluated: 37 PSN and 29 GGN. Median size of PSN solid component was 5 mm (IQR: 4.5, 6). Patients were divided into two groups: 27 in the ssRAB group and 38 in the CTTB group. Diagnostic yield was 85.7% for ssRAB and 89.5% for CTTB (p = 0.646). Sensitivity for malignancy was similar between ssRAB and CTTB (86.4% vs. 88.5%; p = 0.828), with no statistical difference. Complications were more frequent in CTTB with no significant difference (8 vs. 2; p = 0.135).

CONCLUSION

Diagnostic yield for SSN was similarly high for ssRAB and CTTB, with ssRAB presenting less complications and allowing mediastinal staging within the same procedure.

Robotic-assisted bronchoscopy for the diagnosis of peripheral pulmonary lesions: A systematic review and meta-analysis

Robotic-assisted bronchoscopy (RAB) is a newly developed bronchoscopic technique for the diagnosis of peripheral pulmonary lesions (PPLs). The objective of this meta-analysis was to analyze the diagnostic yield and safety of RAB in patients with PPLs. Five databases (PubMed, Embase, Web of Science, CENTRAL, and ClinicalTrials.gov) were searched from inception to April 2023. Two independent investigators screened retrieved articles, extracted data, and assessed the study quality. The pooled diagnostic yield and complication rate were estimated. Subgroup analysis was used to explore potential sources of heterogeneity. Publication bias was assessed using funnel plots and the Egger test. Sensitivity analysis was also conducted to assess the robustness of the synthesized results. A total of 725 lesions from 10 studies were included in this meta-analysis. No publication bias was found. Overall, RAB had a pooled diagnostic yield of 80.4% (95% CI: 75.7%-85.1%). Lesion size of >30 mm, presence of a bronchus sign, and a concentric radial endobronchial ultrasound view were associated with a statistically significantly higher diagnostic yield. Heterogeneity exploration showed that studies using cryoprobes reported better yields than those without cryoprobes (90.0%, 95% CI: 83.2%-94.7% vs. 79.0%, 95% CI: 75.8%-82.2%, p < 0.01). The pooled complication rate was 3.0% (95% CI: 1.6%-4.4%). In conclusion, RAB is an effective and safe technique for PPLs diagnosis. Further high-quality prospective studies still need to be conducted.

Diagnostic yield of endobronchial ultrasound and virtual CT navigational bronchoscopy for biopsy of pulmonary nodules, mediastinal lymph nodes, and thoracic tumors in children

OBJECTIVE

Endobronchial ultrasound-guided transbronchial biopsy and needle aspiration (EBUS-TBB/EBUS-TBNA) are first line investigative modalities for lung and mediastinal pathology in adults. We aimed to characterize and assess the diagnostic yield of EBUS and virtual CT navigation guided biopsies in children.

STUDY DESIGN

This single center, retrospective cohort study included patients who underwent radial or linear EBUS procedures (+/- CT navigation) for biopsy of mediastinal lymph nodes, tumors, and pulmonary nodules. Demographic, procedural, and outcome were collected.

RESULTS

Sixty procedures were performed in 56 patients aged 2-22 years of age between January 2015 and May 2023. The most common indications for biopsy were pulmonary nodules (45%) and hilar/mediastinal lymphadenopathy (33%). For cases in which a final diagnosis was ascertained by any means, the diagnostic yield for linear EBUS (mediastinal pathology) was 76% and the diagnostic yield from radial EBUS (pulmonary nodules and lung masses) was 85%. The most common diagnoses were infection (45%), malignancy (17%), and sarcoidosis (11%). Among patients in whom infection was the final diagnosis, a total of 31 pathogens were identified. Eighteen were identified on bronchoalveolar lavage and an additional 14 pathogens identified on EBUS-TBB, representing an increase of 77% (p < .005). The sensitivity, specificity, negative and positive predictive values for malignancy detection were 73%, 100%, 94%, and 100%, respectively.

CONCLUSION

EBUS-TBB/TBNA is a safe and effective way to diagnose lung and mediastinal pathology in children. Pediatric interventional pulmonology is a growing field offering minimally-invasive diagnostic opportunities for children in whom more invasive procedures were previously the only option.

Robotic-assisted Navigation Bronchoscopy: A Meta-Analysis of Diagnostic Yield and Complications

BACKGROUND

Robotic-assisted navigation bronchoscopy (RANB) is a novel method to biopsy lung nodules, with initial reports demonstrating excellent accuracy. We aimed to evaluate pooled estimates of diagnostic yields and complication rates with RANB by performing a meta-analysis of the available literature.

METHODS

We searched 3 databases, including PubMed, EmBase, and Web of Science. The resulting abstracts were reviewed by 2 investigators. Analyses were performed using random effects models, and diagnostic yield and complication rates were estimated after the Freeman-Tukey transformation.

RESULTS

A total of 23 articles, comprising 1409 patients and 1541 nodules, were included in the final analysis. Mean ages ranged from 63.2 to 69.3 years. The average size of the nodules ranged between 5.9 and 25.0 mm. Most patients (54.0% to 92.0%) had a current or prior smoking history in studies that reported them (n=8). The pooled diagnostic yield was 81.9% (12 studies, 838 nodules, 95% CI: 83.4%-91.0%), and the pooled sensitivity for malignancy was 87.6% (8 studies, 699 nodules, 95% CI: 81.3%-89.5%). The pooled incidence of pneumothorax rates was 0.60% (95% CI: 0.11%-1.35%). The pooled incidence of major bleeding was <0.01%.

CONCLUSION

Diagnostic yield for patients with pulmonary nodules undergoing RANB is high, though may be impacted by the prevalence of malignancy, participant selection, and publication bias. Complication rates, including pneumothoraces and bleeding rates, appear low across all studies. If RANB is available, clinicians should consider utilizing this platform to biopsy pulmonary nodules.

Diagnostic Yield vs Diagnostic Accuracy for Peripheral Lung Biopsy Evaluation: Evidence Supporting a Future Pragmatic End Point

BACKGROUND

Diagnostic yield and accuracy endpoints have been used inconsistently in the evaluation of advanced diagnostic bronchoscopy devices and techniques, limiting between-study comparisons. In addition, diagnostic accuracy can be adjudicated only after prolonged clinical follow-up, which delays reporting on the performance of novel devices.

RESEARCH QUESTION

Will a conservative diagnostic yield definition result in few false-negative initial results to closely approximate diagnostic accuracy and represent a useful outcome for future studies of diagnostic utility?

METHODS

Commonly used definitions of diagnostic yield were applied to a prospective data set of consecutive peripheral pulmonary lesions sampled by navigational bronchoscopy from 2017 to 2019. All consider malignancy to be diagnostic but differ in their classification of nonmalignant biopsy findings, which were subcategorized as specific benign, nonspecific benign, or normal lung. Diagnostic yield calculations were also compared with diagnostic accuracy, defined as the proportion of biopsy specimens deemed diagnostic by each definition that were confirmed accurate through 2 years of follow-up.

RESULTS

A total of 450 biopsy specimens of lesions were analyzed. The prevalence of malignancy was 60.9% (274 of 450). On initial bronchoscopy pathology, there were 227 malignant diagnoses (50.4%), with a single false positive (0.4%). Among 104 biopsy specimens with specific benign findings, only two were false negative for malignancy (1.9%). There were 119 nonspecific benign biopsy specimens, with 46 false negatives for malignancy (38.7%). The discrepancy between diagnostic yield and accuracy was 0.7% for the conservative definition, which only considered malignant or specific benign findings as diagnostic.

INTERPRETATION

A conservative diagnostic yield definition excluding nonspecific benign diagnoses closely approximated diagnostic accuracy through 2 years' follow-up, with a less than 1% discrepancy. Using this conservative yield definition may allow for dissemination of reliable diagnostic utility data without protracted delays needed for follow-up data in this era of rapid technological change in advanced diagnostic bronchoscopy.

Novel electromagnetic navigation bronchoscopy system for the diagnosis of peripheral pulmonary nodules: a prospective, multicentre study

BACKGROUND

Traditional electromagnetic navigation bronchoscopy (ENB) is a real-time image-guided system and used with thick bronchoscopes for the diagnosis of peripheral pulmonary nodules (PPNs). A novel ENB that could be used with thin bronchoscopes was developed. This study aimed to evaluate the diagnostic yield and the experience of using this ENB system in a real clinical scenario.

METHODS

This multicentre study enrolled consecutive patients with PPNs adopting ENB from March 2019 to August 2021. ENB was performed with different bronchoscopes, ancillary techniques and sampling instruments according to the characteristics of the nodule and the judgement of the operator. The primary endpoint was the diagnostic yield. The secondary endpoints included the diagnostic yield of subgroups, procedural details and complication rate.

RESULTS

In total, 479 patients with 479 nodules were enrolled in this study. The median lesion size was 20.9 (IQR, 15.9-25.9) mm. The overall diagnostic yield was 74.9% (359/479). A thin bronchoscope was used in 96.2% (461/479) nodules. ENB in combination with radial endobronchial ultrasound (rEBUS), a guide sheath (GS) and a thin bronchoscope was the most widely used guided method, producing a diagnostic yield of 74.1% (254/343). The median total procedural time was 1325.0 (IQR, 1014.0-1676.0) s. No severe complications occurred.

CONCLUSION

This novel ENB system can be used in combination with different bronchoscopes, ancillary techniques and sampling instruments with a high diagnostic yield and safety profile for the diagnosis of PPNs, of which the combination of thin bronchoscope, rEBUS and GS was the most common method in clinical practice.

TRIAL REGISTRATION NUMBER

NCT03716284.

Diagnostic Performance and Safety Profile of Robotic-assisted Bronchoscopy: A Systematic Review and Meta-Analysis

Rationale: Conventional electromagnetic navigation bronchoscopy and other guided bronchoscopic modalities have a very desirable safety profile, but their diagnostic yield is only 60-70% for pulmonary lesions. Recently, robotic-assisted bronchoscopy (RAB) platforms have been introduced to improve the diagnostic performance of bronchoscopic modalities. Objectives: To determine the diagnostic performance and safety profile of RAB (using shape-sensing and electromagnetic navigation-based platforms) by performing a systematic review and meta-analysis. Methods: The PubMed, Embase, and Google Scholar databases were searched to find studies that reported on the diagnostic performance and/or the safety profile of one of the RAB systems. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Meta-analysis was performed using MedCalc version 20.118. Pooled diagnostic yield was calculated using a Freeman-Tukey transformation. We planned to use a random-effects model if the I2 index was >40%. Results: Twenty-five studies were included: 20 including diagnostic and safety analyses and 5 including only safety analyses. The pooled diagnostic yield of RAB (20 studies, 1,779 lesions) was 84.3% (95% confidence interval, 81.1-87.2%). The I2 index was 65.6%. On the basis of our subgroup analyses, the heterogeneity was likely driven by differences in study designs (prospective vs. retrospective) and procedural protocols (such as different RAB systems). Lesion size > 2 cm, the presence of a computed tomography bronchus sign, and concentric radial endobronchial ultrasound view were associated with a statistically significant increase in the odds of diagnosis with RAB. The overall rates of pneumothorax, need for tube thoracostomy, and significant hemorrhage were 2.3%, 1.2%, and 0.5%, respectively. Conclusions: RAB systems have significantly increased the diagnostic yield of navigational bronchoscopy compared with conventional systems such as electromagnetic navigation bronchoscopy, but well-designed prospective studies are needed to better understand the impact of various factors, such as the use of three-dimensional imaging modalities, cryobiopsy, and specific ventilatory protocols, on the diagnostic yield of RAB.

Navigational Bronchoscopy versus Computed Tomography-guided Transthoracic Needle Biopsy for the Diagnosis of Indeterminate Lung Nodules: protocol and rationale for the VERITAS multicenter randomized trial

Background

Lung nodule incidence is increasing. Many nodules require biopsy to discriminate between benign and malignant etiologies. The gold-standard for minimally invasive biopsy, computed tomography-guided transthoracic needle biopsy (CT-TTNB), has never been directly compared to navigational bronchoscopy, a modality which has recently seen rapid technological innovation and is associated with improving diagnostic yield and lower complication rate. Current estimates of the diagnostic utility of both modalities are based largely on non-comparative data with significant risk for selection, referral, and publication biases.

Methods

The VERITAS trial (na V igation E ndoscopy to R each Indeterminate lung nodules versus T ransthoracic needle A spiration, a randomized controlled S tudy) is a multicenter, 1:1 randomized, parallel-group trial designed to ascertain whether electromagnetic navigational bronchoscopy with integrated digital tomosynthesis is noninferior to CT-TTNB for the diagnosis of peripheral lung nodules 10-30 mm in diameter with pre-test probability of malignancy of at least 10%. The primary endpoint is diagnostic accuracy through 12 months follow-up. Secondary endpoints include diagnostic yield, complication rate, procedure duration, need for additional invasive diagnostic procedures, and radiation exposure.

Discussion

The results of this rigorously designed trial will provide high-quality data regarding the management of lung nodules, a common clinical entity which often represents the earliest and most treatable stage of lung cancer. Several design challenges are described. Notably, all nodules are centrally reviewed by an independent interventional pulmonology and radiology adjudication panel relying on pre-specified exclusions to ensure enrolled nodules are amenable to sampling by both modalities while simultaneously protecting against selection bias favoring either modality. Conservative diagnostic yield and accuracy definitions with pre-specified criteria for what non-malignant findings may be considered diagnostic were chosen to avoid inflation of estimates of diagnostic utility.

Trial registration

ClinicalTrials.gov NCT04250194.

A Multicenter, Single-Arm, Prospective Trial Assessing the Diagnostic Yield of Electromagnetic Bronchoscopic and Transthoracic Navigation for Peripheral Pulmonary Nodules

Rationale: Strict adherence to procedural protocols and diagnostic definitions is critical to understand the efficacy of new technologies. Electromagnetic navigational bronchoscopy (ENB) for lung nodule biopsy has been used for decades without a solid understanding of its efficacy, but offers the opportunity for simultaneous tissue acquisition via electromagnetic navigational transthoracic biopsy (EMN-TTNA) and staging via endobronchial ultrasound (EBUS). Objective: To evaluate the diagnostic yield of EBUS, ENB, and EMN-TTNA during a single procedure using a strict a priori definition of diagnostic yield with central pathology adjudication. Methods: A prospective, single-arm trial was conducted at eight centers enrolling participants with pulmonary nodules (<3 cm; without computed tomography [CT]- and/or positron emission tomography-positive mediastinal lymph nodes) who underwent a staged procedure with same-day CT, EBUS, ENB, and EMN-TTNA. The procedure was staged such that, when a diagnosis had been achieved via rapid on-site pathologic evaluation, the procedure was ended and subsequent biopsy modalities were not attempted. A study finding was diagnostic if an independent pathology core laboratory confirmed malignancy or a definitive benign finding. The primary endpoint was the diagnostic yield of the combination of CT, EBUS, ENB, and EMN-TTNA. Measurements and Main Results: A total of 160 participants at 8 centers with a mean nodule size of 18 ± 6 mm were enrolled. The diagnostic yield of the combined procedure was 59% (94 of 160; 95% confidence interval [CI], 51-66%). Nodule regression was found on same-day CT in 2.5% of cases (4 of 160; 95% CI, 0.69-6.3%), and EBUS confirmed malignancy in 7.1% of cases (11 of 156; 95% CI, 3.6-12%). The yield of ENB alone was 49% (74 of 150; 95% CI, 41-58%), that of EMN-TTNA alone was 27% (8 of 30; 95% CI, 12-46%), and that of ENB plus EMN-TTNA was 53% (79 of 150; 95% CI, 44-61%). Complications included a pneumothorax rate of 10% and a 2% bleeding rate. When EMN-TTNA was performed, the pneumothorax rate was 30%. Conclusions: The diagnostic yield for ENB is 49%, which increases to 59% with the addition of same-day CT, EBUS, and EMN-TTNA, lower than in prior reports in the literature. The high complication rate and low diagnostic yield of EMN-TTNA does not support its routine use. Clinical trial registered with www.clinicaltrials.gov (NCT03338049).

Diagnostic Yield of Cone-beam-Derived Augmented Fluoroscopy and Ultrathin Bronchoscopy Versus Conventional Navigational Bronchoscopy Techniques

BACKGROUND

Pulmonary nodules suspicious for lung cancer are frequently diagnosed. Evaluating and optimizing the diagnostic yield of lung nodule biopsy is critical as innovation in bronchoscopy continues to progress.

METHODS

This is a retrospective cohort study. Consecutive patients undergoing guided bronchoscopy for suspicious pulmonary nodule(s) between February 2020 and July 2021 were included. The cone-beam computed tomography (CBCT)+ radial endobronchial ultrasound (r-EBUS) group had their procedure using CBCT-derived augmented fluoroscopy along with r-EBUS. The CBCT+ ultrathin bronchoscope (UTB)+r-EBUS group had the same procedure but with the use of an ultrathin bronchoscope. The r-EBUS group underwent r-EBUS guidance without CBCT or augmented fluoroscopy. We used multivariable logistic regression to compare diagnostic yield, adjusting for confounding variables.

RESULTS

A total of 116 patients were included. The median pulmonary lesion diameter was 19.5 mm (interquartile range, 15.0 to 27.5 mm), and 91 (78.4%) were in the peripheral half of the lung. Thirty patients (25.9%) underwent CBCT+UTB, 27 (23.3%) CBCT, and 59 (50.9%) r-EBUS alone with unadjusted diagnostic yields of 86.7%, 70.4%, and 42.4%, respectively ( P <0.001). The adjusted diagnostic yields were 85.0% (95% CI, 68.6% to 100%), 68.3% (95% CI, 50.1% to 86.6%), and 44.5% (95% CI, 31.0% to 58.0%), respectively. There was significantly more virtual navigational bronchoscopy use in the r-EBUS group (45.8%) compared with the CBCT+UTB (13.3%) and CBCT (18.5%) groups, respectively. CBCT procedures required dose area product radiation doses of 7602.5 µGym 2 .

CONCLUSION

Compared with the r-EBUS group, CBCT + UTB + r-EBUS was associated with higher navigational success, fewer nondiagnostic biopsy results, and a higher diagnostic yield. CBCT procedures are associated with a considerable radiation dose.

The Effect of Definitions and Cancer Prevalence on Diagnostic Yield Estimates of Bronchoscopy: A Simulation-based Analysis

Rationale: Studies of bronchoscopy have reported diagnostic yield (DY) using different calculation methods, which has hindered comparisons across studies. Objectives: To quantify the effect of the variability of four methods on DY estimates of bronchoscopy. Methods: We performed a simulation-based analysis of patients undergoing bronchoscopy using variations around base case assumptions for cancer prevalence (60%), distribution of nonmalignant findings, and degree of follow-up information at a fixed sensitivity of bronchoscopy for malignancy (80%). We calculated DY, the rate of true positives and true negatives (TNs), using four methods. Method 1 considered malignant and specific benign findings at index bronchoscopy as true positives and TNs, respectively. Method 2 included nonspecific benign findings as TNs. Method 3 considered nonspecific benign findings cases as TNs only if follow-up confirmed benign disease. Method 4 counted all cases with a nonmalignant diagnosis as TNs if follow-up confirmed benign disease. A scenario analysis and probabilistic sensitivity analysis were conducted to demonstrate the effect of parameter estimates on DY. A change in DY of >10% was considered clinically meaningful. Results: Across all pairwise comparisons of the four methods, a DY difference of >10% was observed in 76.7% of cases (45,992 of 60,000 comparisons). Method 4 resulted in DY estimates that were >10% higher than estimates made with other methods in >90% of scenarios. Variation in cancer prevalence had a large effect on DY. Conclusions: Across a wide range of clinical scenarios, the categorization of nonmalignant findings at index bronchoscopy and cancer prevalence had the largest impact on DY. The large variability in DY estimates across the four methods limits the interpretation of bronchoscopy studies and warrants standardization.

Real-World Impact of Robotic-Assisted Bronchoscopy on the Staging and Diagnosis of Lung Cancer: The Shape of Current and Potential Opportunities

The approach to peripheral pulmonary lesions (PPL) has been evolving continuously. Advanced bronchoscopic navigational techniques have improved the airway-based approaches to these lesions. Robotic Assisted Bronchoscopy (RAB) can be considered the current pinnacle of this evolution; allowing for a safer approach to sampling lesions previously considered outside of bronchoscopic reach. We present a comprehensive review of the changing epidemiology of lung cancer and the importance of early tissue sampling, the evolution of sampling and navigational bronchoscopic techniques, technical considerations and evidence pertaining to the use of RAB, and adjunct techniques in the diagnosis of lung cancer. Complications and future applications of RAB are also discussed.

Reporting Standards for Diagnostic Testing: Guidance for Authors From Editors of Respiratory, Sleep, and Critical Care Journals

Diagnostic testing is fundamental to medicine. However, studies of diagnostic testing in respiratory medicine vary significantly in terms of their methodology, definitions, and reporting of results. This has led to often conflicting or ambiguous results. To address this issue, a group of 20 respiratory journal editors worked to develop reporting standards for studies of diagnostic testing based on a rigorous methodology to guide authors, peer reviewers, and researchers when conducting studies of diagnostic testing in respiratory medicine. Four key areas are covered, including defining the reference standard of truth, measures of dichotomous test performance when used for dichotomous outcomes, measures of multichotomous test performance for dichotomous outcomes, and what constitutes a useful definition of diagnostic yield. The importance of using contingency tables for reporting results is addressed with examples from the literature. A practical checklist is provided as well for reporting studies of diagnostic testing.

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.

Diagnostic outcomes of robotic-assisted bronchoscopy for pulmonary lesions in a real-world multicenter community setting

BACKGROUND

Robot-assisted bronchoscopy (RAB) is among the newest bronchoscopic technologies, allowing improved visualization and access for small and hard-to-reach nodules. RAB studies have primarily been conducted at academic centers, limiting the generalizability of results to the broader real-world setting, while variability in diagnostic yield definitions has impaired the validity of cross-study comparisons. The objective of this study was to determine the diagnostic yield and sensitivity for malignancy of RAB in patients with pulmonary lesions in a community setting and explore the impact of different definitions on diagnostic yield estimates.

METHODS

Data were collected retrospectively from medical records of patients ≥ 21 years who underwent bronchoscopy with the Monarch® Platform (Auris Health, Inc., Redwood City, CA) for biopsy of pulmonary lesions at three US community hospitals between January 2019 and March 2020. Diagnostic yield was calculated at the index RAB and using 12-month follow-up data. At index, all malignant and benign (specific and non-specific) diagnoses were considered diagnostic. After 12 months, benign non-specific cases were considered diagnostic only when follow-up data corroborated the benign result. An alternative definition at index classified benign non-specific results as non-diagnostic, while an alternative 12-month definition categorized index non-diagnostic cases as diagnostic if no malignancy was diagnosed during follow-up.

RESULTS

The study included 264 patients. Median lesion size was 19.3 mm, 58.9% were peripherally located, and 30.1% had a bronchus sign. Samples were obtained via Monarch in 99.6% of patients. Pathology led to a malignant diagnosis in 115 patients (43.6%), a benign diagnosis in 110 (41.7%), and 39 (14.8%) non-diagnostic cases. Index diagnostic yield was 85.2% (95% CI: [80.9%, 89.5%]) and the 12-month diagnostic yield was 79.4% (95% CI: [74.4%, 84.3%]). Alternative definitions resulted in diagnostic yield estimates of 58.7% (95% CI: [52.8%, 64.7%]) at index and 89.0% (95% CI: [85.1%, 92.8%]) at 12 months. Sensitivity for malignancy was 79.3% (95% CI: [72.7%, 85.9%]) and cancer prevalence was 58.0% after 12 months.

CONCLUSIONS

RAB demonstrated a high diagnostic yield in the largest study to date, despite representing a real-world community population with a relatively low prevalence of cancer. Alternative definitions had a considerable impact on diagnostic yield estimates.

Diagnostic yield and safety of navigation bronchoscopy: A systematic review and meta-analysis

BACKGROUND

Navigation bronchoscopy has seen rapid development in the past decade in terms of new navigation techniques and multi-modality approaches utilizing different techniques and tools. This systematic review analyses the diagnostic yield and safety of navigation bronchoscopy for the diagnosis of peripheral pulmonary nodules suspected of lung cancer.

METHODS

An extensive search was performed in Embase, Medline and Cochrane CENTRAL in May 2022. Eligible studies used cone-beam CT-guided navigation (CBCT), electromagnetic navigation (EMN), robotic navigation (RB) or virtual bronchoscopy (VB) as the primary navigation technique. Primary outcomes were diagnostic yield and adverse events. Quality of studies was assessed using QUADAS-2. Random effects meta-analysis was performed, with subgroup analyses for different navigation techniques, newer versus older techniques, nodule size, publication year, and strictness of diagnostic yield definition. Explorative analyses of subgroups reported by studies was performed for nodule size and bronchus sign.

RESULTS

A total of 95 studies (n = 10,381 patients; n = 10,682 nodules) were included. The majority (n = 63; 66.3%) had high risk of bias or applicability concerns in at least one QUADAS-2 domain. Summary diagnostic yield was 70.9% (95%-CI 68.4%-73.2%). Overall pneumothorax rate was 2.5%. Newer navigation techniques using advanced imaging and/or robotics(CBCT, RB, tomosynthesis guided EMN; n = 24 studies) had a statistically significant higher diagnostic yield compared to longer established techniques (EMN, VB; n = 82 studies): 77.5% (95%-CI 74.7%-80.1%) vs 68.8% (95%-CI 65.9%-71.6%) (p < 0.001).Explorative subgroup analyses showed that larger nodule size and bronchus sign presence were associated with a statistically significant higher diagnostic yield. Other subgroup analyses showed no significant differences.

CONCLUSION

Navigation bronchoscopy is a safe procedure, with the potential for high diagnostic yield, in particular using newer techniques such as RB, CBCT and tomosynthesis-guided EMN. Studies showed a large amount of heterogeneity, making comparisons difficult. Standardized definitions for outcomes with relevant clinical context will improve future comparability.

Diagnostic efficacy of cryobiopsy for peripheral pulmonary lesions: A propensity score analysis

OBJECTIVES

Recently introduced cryobiopsy can provide quantitatively and qualitatively excellent specimens. However, few studies have directly compared the diagnostic yield of cryobiopsy for peripheral pulmonary lesions (PPLs) with that of conventional sampling methods.

MATERIAL AND METHODS

We retrospectively reviewed data from consecutive patients who underwent diagnostic bronchoscopy using radial endobronchial ultrasound and virtual bronchoscopic navigation for PPLs (October 2015 to September 2020). Patients who underwent cryobiopsy were assigned to the cryo group, whereas those who did not undergo cryobiopsy were assigned to the conventional group. The diagnostic outcomes of both groups were compared using propensity score analyses.

RESULTS

A total of 2,724 cases were identified, including 492 and 2,232 cases in the cryo and conventional groups, respectively. Propensity scoring was performed to match baseline characteristics, and 481 pairs of cases were selected for each matched group (m-group). The diagnostic yield was significantly higher in the m-cryo group than in the m-conventional group (89.2% vs. 77.6%, odds ratio [OR] = 2.36 [95% confidence interval [CI] = 1.65-3.38], P < 0.001). Propensity score stratification (OR = 2.35 [95% CI = 1.71-3.23]) and regression adjustment (OR = 2.54 [95% CI = 1.83-3.52]) also demonstrated the diagnostic advantages of cryobiopsy. The subgroup analysis revealed that cryobiopsy was notably effective for lesions in the middle lobe/lingula, right/left lower lobe, lesions with ground-glass opacity, and lesions invisible on chest radiography. Although there were more cases of grade 2 and 3 bleeding in the m-cryo group than in the m-conventional group (38.0% vs. 10.2% and 1.5% vs. 0.8%, respectively; P < 0.001), no grade 4 bleeding was observed.

CONCLUSION

The propensity score analyses revealed that cryobiopsy was associated with a higher diagnostic yield for PPLs than conventional sampling methods. However, increased bleeding risk should be noted as a potential complication.

The additional diagnostic value of virtual bronchoscopy navigation in patients with pulmonary nodules - The NAVIGATOR study

BACKGROUND

The number of solitary pulmonary nodules to be evaluated is expected to increase and therefore we need to improve diagnostic and therapeutic tools to approach these nodules. To prevent patients from futile invasive procedures and receiving treatment without histological confirmation of cancer, we evaluated the value of virtual bronchoscopy navigation to obtain a diagnosis of the solitary pulmonary nodule in a real-world clinical setting.

METHODS

In the NAVIGATOR single center, prospective, observational cohort study patients underwent a virtual bronchoscopy navigation procedure with or without guide sheet tunnelling to assess a solitary pulmonary nodule. Nodules were considered not accessible if a diagnosis could not be obtained by either by CT-guided transthoracic biopsy or conventional bronchoscopy.

RESULTS

Between February 2021 and January 2022 35 patients underwent the virtual bronchoscopy navigation procedure. The overall diagnostic yield was 77% and was dependent on size of the nodule and chosen path, with highest yield in lesions with an airway path. Adverse events were few and manageable.

CONCLUSION

Virtual bronchoscopy navigation with or without sheet tunnelling is a new technique with a good diagnostic yield, also in patients in whom previously performed procedures failed to establish a diagnosis and/or alternative procedures are considered not feasible based on expected yield and/or safety. Preventing futile or more invasive procedures like surgery or transthoracic punctures with a higher complication rate is beneficial for patients, and allowed treatment adaptation in two-third of the analyzed patient population.

Robotic-assisted bronchoscopy versus CT-guided transthoracic biopsy for diagnosis of pulmonary nodules

BACKGROUND AND OBJECTIVE

Currently, computed tomography-guided transthoracic biopsy (CTTB) is the most accurate diagnostic approach for pulmonary nodules suspected of malignancy. Traditional bronchoscopy has shown suboptimal diagnostic sensitivity, but the emergence of robotic-assisted bronchoscopy (RAB) has the potential to improve diagnostic accuracy, maximize diagnostic yield and complete mediastinal and hilar staging in a single procedure. We aim to assess the efficacy and diagnostic performance of RAB compared to CTTB for diagnosing pulmonary nodules suspected of lung cancer.

METHODS

A multicenter retrospective review of consecutive patients who underwent RAB and CTTB for evaluating pulmonary nodules from January 2019 to March 2021 at Mayo Clinic Florida and Mayo Clinic Rochester, United States. Clinical and demographic information, nodule characteristics, outcomes and complications were compared between RAB and CTTB.

RESULTS

A total of 225 patients were included: 113 in the RAB group and 112 in the CTTB group. Overall diagnostic yield was 87.6% for RAB and 88.4% for CTTB. For malignant disease, RAB had a sensitivity of 82.1% and a specificity of 100%, CTTB had a sensitivity of 88.5% and a specificity of 100%. Complication rate was significantly higher for CTTB compared to RAB (17% vs. 4.4%; p = 0.002).

CONCLUSION

RAB, when available, can be as accurate as CTTB for sampling pulmonary nodules with similar or reduced complications and should be considered as a means for nodule biopsy, particularly when mediastinal staging is also clinically warranted.

Shape-Sensing Robotic-Assisted Bronchoscopy vs Digital Tomosynthesis-Corrected Electromagnetic Navigation Bronchoscopy: A Comparative Cohort Study of Diagnostic Performance

BACKGROUND

Electromagnetic navigational bronchoscopy has been the dominant bronchoscopic technology for targeting small peripheral lesions and now includes digital tomosynthesis-electromagnetic navigational bronchoscopy (DT-ENB), allowing near-real-time intraprocedural nodule visualization. Shape-sensing robotic-assisted bronchoscopy (ssRAB), with improved catheter stability and articulation recently became available. Although the diagnostic performance of these two methods seems higher than that of legacy systems, data remain limited. We sought to compare the diagnostic yield of these two novel platforms after their introduction at our institution.

RESEARCH QUESTION

Does the diagnostic yield of ssRAB differ significantly from that of DT-ENB in patients undergoing biopsy of peripheral pulmonary lesions (PPLs)?

STUDY DESIGN AND METHODS

This retrospective comparative cohort study analyzed prospectively collected data on consecutive procedures performed with DT-ENB and ssRAB in their first 6 months of use at our institution. Biopsies were considered diagnostic if histopathologic analysis revealed malignancy or specific benign features that readily explained the presence of a PPL. Nonspecific inflammation, normal lung or airway, and atypia not diagnostic of malignancy were considered nondiagnostic.

RESULTS

SSRAB was used to biopsy 143 PPLs in 133 patients and DT-ENB was used to biopsy 197 PPLs in 170 patients. Diagnostic yield was 77% for ssRAB (110 of 143 PPLs) and 80% (158 of 197 PPLs) for DT-ENB (OR, 0.8; 95% CI, 0.5-1.4; P = .4). Median lesion diameters were 17 and 19 mm, respectively. No difference in diagnostic yield was found after adjustment for lesion size, bronchus sign, peripheral vs middle third location, and sex. Pneumothorax complicated 1.5% of ssRAB and 1.8% of DT-ENB procedures (P = .86).

INTERPRETATION

SSRAB and DT-ENB showed comparable diagnostic yields and safety profiles in this comparative cohort study.

Endobronchial Ultrasound Transbronchial Needle Aspiration With a 19-Gauge Needle vs 21- and 22-Gauge Needles for Mediastinal Lymphadenopathy

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is commonly used to evaluate mediastinal lymphadenopathy. Studies focusing on malignant lymphadenopathy have compared 21- and 22-gauge (21G and 22G, respectively) needles and have not identified an advantage of one needle size over the other in terms of diagnostic yield.

RESEARCH QUESTION

Does the 19-gauge (19G) EBUS needle offer greater diagnostic yield and sensitivity vs the 21G and 22G EBUS needles for a diagnosis of sarcoidosis, lymphoma, or mediastinal lymphadenopathy not yet diagnosed?

STUDY DESIGN AND METHODS

This study retrospectively examined records of 730 patients from the Stather Canadian Outcomes Registry for Chest Procedures (SCOPE) database who underwent EBUS-TBNA for a diagnosis of suspected sarcoidosis, lymphoma, or mediastinal lymphadenopathy not yet diagnosed. A propensity score analysis of two groups was performed. One group comprised patients undergoing EBUS-TBNA with a 19G needle, the other with a 21G or 22G needle. Cases for analysis were selected with a 1:2 ratio of 19G vs 21/22G using logistic regression and random matching with all eligible 19G cases included.

RESULTS

There were 137 patients (312 targets) in the 19G group and 274 patients (631 targets) in the 21/22G group in the propensity score analysis. The diagnostic yield was 107 of 137 (78.1%) in the 19G group vs 194 of 274 (70.8%) in the 21/22G group (difference, 7.3%; 95% CI, -1.9 to 15.6; P = .116). The sensitivity of EBUS-TBNA for sarcoidosis was 80 of 84 (95.2%) in the 19G group vs 150 of 156 (96.2%) in the 21/22G group (difference, 1.0%; 95% CI, -4.2 to 8.2; P = .71). In patients with a final diagnosis of lymphoma, EBUS was diagnostic in 10 of 13 (76.9%) in the 19G group vs 12 of 12 (100%) in the 21/22G group (difference, 23.1%; 95% CI, -5.4 to 50.3; P = .08).

INTERPRETATION

The study did not identify an advantage of the 19G EBUS needle over the 21/22G EBUS needles for diagnostic yield nor sensitivity for sarcoidosis or lymphoma.