Factors Associated with Diagnostic Accuracy of Robotic Bronchoscopy with 12-month Follow-up

The incremental contribution of mobile cone-beam computed tomography to the tool-lesion relationship during shape-sensing robotic-assisted bronchoscopy

Introduction

This study aims to answer the question of whether adding mobile cone-beam computed tomography (mCBCT) imaging to shape-sensing robotic-assisted bronchoscopy (ssRAB) translates into a quantifiable improvement in the tool-lesion relationship.

Methods

Data from 102 peripheral lung lesions with ≥2 sequential mCBCT orbital spins and from 436 lesions with 0-1 spins were prospectively captured and retrospectively analysed. The primary outcome was the tool-lesion relationship status across the first and the last mCBCT spins. Secondary outcomes included 1) the change in distance between the tip of the sampling tool and the centre of the lesion between the first and the last spins and 2) the per-lesion diagnostic yield.

Results

Compared to lesions requiring 0-1 spins, lesions requiring ≥2 spins were smaller and had unfavourable bronchus sign and intra-operative sonographic view. On the first spin, 54 lesions (53%) were designated as non-tool-in-lesion (non-TIL) while 48 lesions (47%) were designated as TIL. Of the 54 initially non-TIL cases, 49 (90%) were converted to TIL status by the last spin. Overall, on the last spin, 96 out of 102 lesions (94%) were defined as TIL and six out of 102 lesions (6%) were defined as non-TIL (p<0.0001). The mean distance between the tool and the centre of the lesion decreased from 10.4 to 6.6 mm between the first and last spins (p<0.0001). The overall diagnostic yield was 77%.

Conclusion

Targeting traditionally challenging lung lesions, intra-operative volumetric imaging allowed for the conversion of 90% of non-TIL status to TIL. Guidance with mCBCT resulted in a significant decrease in the distance between the tip of the needle to lesion centre.

Bronchoscopic treatment of early-stage peripheral lung cancer

PURPOSE OF REVIEW

This review article focuses on bronchoscopic treatment of early-stage peripheral lung cancer.

RECENT FINDINGS

Bronchoscopic treatment modalities have garnered considerable attention for early-stage lung cancer. Studies using photodynamic therapy, thermal vapor ablation, laser ablation, cryoablation, and intra-tumoral injection have recently been published. However, the evidence supporting these approaches largely derives from single-arm studies with small sample sizes. Based on the IDEAL-D framework, no technology has progressed passed the idea phase (1). The main weakness of these technologies to date is lack of evidence suggesting they can achieve local control. Presently, no bronchoscopic intervention for lung cancer has sufficient data to warrant its use as part of the standard of care.

SUMMARY

Despite notable progress, current technologies remain suboptimal, and there is insufficient evidence to support their use outside of a research setting.

Characterizing a learning curve for robotic-assisted bronchoscopy: Analysis of skills acquisition in a high-volume academic center

OBJECTIVE

Shape-sensing robotic-assisted bronchoscopy is an emerging technology for the sampling of pulmonary lesions. We seek to characterize the shape-sensing robotic-assisted bronchoscopy learning curve at an academic center.

METHODS

Shape-sensing robotic-assisted bronchoscopy procedures performed by 9 proceduralists at a single institution were analyzed. Cumulative sum analyses were performed to examine diagnostic sampling and procedure time over each operator's first 50 cases, with the acceptable yield threshold set to 73%.

RESULTS

During the study period, 442 patients underwent sampling of 551 lesions. Each operator sampled 61 lesions (interquartile range, 60-63 lesions). Lesion size was 1.90 cm (interquartile range, 1.33-2.80 cm). The median procedure time for single-target cases decreased from 62 minutes during the first 10 cases to 39 minutes after case 40 (P < .001). The overall diagnostic yield was 72% (range, 58%-83%). Six of 9 operators achieved proficiency over the study period. An aggregated cumulative sum analysis of those who achieved competency demonstrated a steep improvement between lesions 1 and 21 and crossing of the competency threshold by lesion 25. Temporal analysis of yield-related lesion characteristics demonstrated that at approximately lesion 20, more challenging lesions were increasingly targeted, as evidenced by smaller target size, higher rates of unfavorable radial endobronchial ultrasound views, and a negative bronchus sign.

CONCLUSIONS

Skills acquisition in shape-sensing robotic-assisted bronchoscopy is variable. Approximately half of proceduralists become facile with the technology within 25 lesions. After the initial learning phase, operators increasingly target lesions with more challenging features. Overall, these findings can inform certification and competency standards and provide new users with expectations related to performance over time.

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.

Robotic-Assisted Bronchoscopy: A Comprehensive Review of System Functions and Analysis of Outcome Data

The past two decades have witnessed a revolutionary era for peripheral bronchoscopy. Though the initial description of radial endobronchial ultrasound can be traced back to 1992, it was not until the mid-2000s that its utilization became commonplace, primarily due to the introduction of electromagnetic navigation (EMN) bronchoscopy. While the diagnostic yield of EMN-assisted sampling has shown substantial improvement over historical fluoroscopy-assisted bronchoscopic biopsy, its diagnostic yield plateaued at around 70%. Factors contributing to this relatively low diagnostic yield include discrepancies in computed tomography to body divergence, which led to unsuccessful lesion localization and resultant unsuccessful sampling of the lesion. Furthermore, much of peripheral bronchoscopy utilized a plastic extended working channel whose tips were difficult to finely aim at potential targets. However, the recent introduction of robotic-assisted bronchoscopy, and its associated stability within the peripheral lung, has ignited optimism for its potential to significantly enhance the diagnostic performance for peripheral lesions. Moreover, some envision this technology eventually playing a pivotal role in the therapeutic delivery to lung tumors. This review aims to describe the currently available robotic-assisted bronchoscopy technologies and to discuss the existing scientific evidence supporting these.

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.

Unlocking the potential of robotic-assisted bronchoscopy: overcoming challenging anatomy and locations

Robotic-assisted bronchoscopy (RAB) was recently added to the armamentarium of tools used in sampling peripheral lung nodules. Protocols and guidelines have since been published advocating use of large oral artificial airways, use of confirmatory technologies such as radial endobronchial ultrasound (R-EBUS), and preferably limiting sampling to pulmonary parenchymal lesions. We present three clinical cases where RAB was used unconventionally to sample pulmonary nodules in unusual locations and in patients with challenging airway anatomy. In case 1, we introduced the ion catheter through a nasal airway in a patient with trismus. In case 2, we established a diagnosis by sampling a station 5 lymph node, and in case 3, we sampled a lesion located behind an airway stump from previous thoracic surgery. All three patients would have presented significant challenges for alternative biopsy modalities such as CT-guided needle biopsy or video-assisted thoracic surgery.

Advances in navigating to the nodule and targeting

PURPOSE OF REVIEW

The multitude of available platforms and imaging modalities for navigational bronchoscopy, in combination with the various sampling tools that can be used intra-procedurally, is complex. This review seeks to describe the recent developments in peripheral bronchoscopy in regards to navigation, imaging, and sampling target lesions in the pulmonary parenchyma.

RECENT FINDINGS

Robotic assisted bronchoscopy has improved navigation to the peripheral airways for sampling of peripheral parenchymal lesions. These navigational platforms use innovative technology utilizing electromagnetic navigation and shape-sensing technology for guidance. The greatest improvement has been the stabilization of the robotic scope in the periphery to allow for accurate sampling. Despite improvements in these platforms, limitations of CT to body divergence continue to impact navigation to the lesion and therefore diagnostic yield of the procedure. Advanced intraprocedural imaging with cone beam CT or augmented fluoroscopy has been a recent focus to improve this area. Further, the adoption of newer sampling tools, such as cryobiopsy, offers the possibility of increased diagnostic yield.

SUMMARY

The developments in advanced bronchoscopy will impact the role of biopsy in the diagnosis of peripheral pulmonary parenchymal lesions.

Anesthetic considerations in interventional pulmonology

PURPOSE OF REVIEW

In this review, we highlight the important anesthetic consideration that relate to interventional bronchoscopic procedures for the management of central airway obstruction due to anterior mediastinal masses, endoluminal endobronchial obstruction, peripheral bronchoscopy for diagnosis and treatment of lung nodules, bronchoscopic lung volume reduction and medical pleuroscopy for diagnosis and management of pleural diseases.

RECENT FINDINGS

The advent of the field of Interventional Pulmonology has allowed for minimally invasive options for patients with a wide range of lung diseases which at times have replaced more invasive surgical procedures. Ongoing research has shed light on advancement in anesthetic techniques and management strategies that have increased the safety during peri-operative management during these complex procedures. Current evidence focusing on the anesthetic techniques is presented here.

SUMMARY

The field of Interventional Pulmonology requires a tailored anesthetic approach. Recent advancements and ongoing research have focused on expanding the partnership between the anesthesiologist and interventional pulmonologists which has led to improved outcomes for patients undergoing these procedures.

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.

Accuracy of Preliminary Pathology for Robotic Bronchoscopic Biopsy

BACKGROUND

Diagnosis and treatment of peripheral pulmonary lesions (PPLs) currently require at least 2 procedures. An all-in-1 approach would require diagnosing malignancy with preliminary cytology results. This study investigated the concordance between preliminary cytology and final pathology results in biopsies of PPLs obtained by shape-sensing robotic-assisted bronchoscopy (ssRAB).

METHODS

This study was a retrospective, consecutive, single-arm, single-center study of 110 ssRABs for PPLs. Concordance was defined as agreement between preliminary cytology and final pathology results. Accuracy, sensitivity, specificity, positive and negative predictive values, and safety outcomes were examined.

RESULTS

The concordance was 89% for needle biopsies, 85% for forceps biopsies, and 92% overall, with substantial agreement. There was no significant association of concordance with patients' demographics or lesion characteristics. Preliminary cytology resulted in a malignant diagnosis in 70%, a nonmalignant diagnosis in 4%, and a nondiagnostic result in 26%, with accuracy of 86% and sensitivity of 84%. The total complication rate was 3.6%, with a pneumothorax rate of 1.8%.

CONCLUSIONS

This study compared the concordance of preliminary pathology results with final pathology results for ssRAB biopsies in PPLs. The results showed that preliminary samples have a high concordance with final pathology results and may enable management of PPLs with a single anesthetic procedure including biopsy, staging, and treatment.

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.

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.

Computed Tomography Bronchus Sign Subclassification during Radial Endobronchial Ultrasound-Guided Transbronchial Biopsy: A Retrospective Analysis

The presence of computed tomography bronchus sign (CT-BS) substantially increases the diagnostic yield of peripheral pulmonary lesions. However, the clinical significance of subdividing CT-BS remains controversial. We classified bronchus types on CT into six subtypes (CT-BS group I: types Ia–Ic with the bronchus connected within the lesion, group II: types IIa–IIc without connection) to clarify the differences in their characteristics and investigate the factors associated with diagnosis during radial endobronchial ultrasound (rEBUS)-guided bronchoscopy. In total, 1021 cases were analyzed. Our findings in diagnostic yields were that in CT-BS group I, penetrating type Ic was inferior to obstructed type Ia and narrowing type Ib (59.0% vs. 80.0% and 76.3%, p < 0.001, p = 0.004); in CT-BS group II, compressed type IIa showed no difference when compared with invisible type IIb and uninvolved type IIc (IIa: 52.8% vs. IIb: 46.3% and IIc: 35.7%, p = 0.253). Multivariable analysis revealed that bronchus type (types Ia and Ib vs. Ic) was a significant independent predictor of successful diagnosis in CT-BS group I (odds ratio, 1.78; 95% confidence interval, 1.04–3.05; p = 0.035), along with known factors such as rEBUS visualization. CT-BS subclassification may provide useful information regarding the bronchoscopic technique to facilitate accurate diagnosis.

Robotic Bronchoscopy for the Diagnosis of Pulmonary Lesions

Pulmonary nodules (lesions <3 cm in size) are commonly identified on computed tomographic scans, but radiographic features alone are inadequate to reliably differentiate between benign and malignant etiologies. Therefore, tissue biopsy remains the standard approach to determine the appropriate treatment course for many patients with pulmonary nodules. Although percutaneous biopsy is highly accurate, it poses substantial risks of procedural complications, including pneumothorax and bleeding. Robotic bronchoscopy has recently been developed to overcome many of the limitations of previous navigational platforms. Here, we explore the currently available systems for robotic bronchoscopy-in particular, electromagnetic-navigation robotic-assisted bronchoscopy and shape-sensing robotic-assisted bronchoscopy.

Robotic Bronchoscopy: Review of Three Systems

Robotic bronchoscopy (RB) has been shown to improve access to smaller and more peripheral lung lesions, while simultaneously staging the mediastinum. Pre-clinical studies demonstrated extremely high diagnostic yields, but real-world RB yields have yet to fully matched up in prospective studies. Despite this, RB technology has rapidly evolved and has great potential for lung-cancer diagnosis and even treatment. In this article, we review the historical and present challenges with RB in order to compare three RB systems.