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.

Robotic versus Electromagnetic bronchoscopy for pulmonary LesIon AssessmeNT: the RELIANT pragmatic randomized trial

BACKGROUND

Robotic-assisted bronchoscopy has recently emerged as an alternative to electromagnetic navigational bronchoscopy for the evaluation of peripheral pulmonary lesions. While robotic-assisted bronchoscopy is proposed to have several advantages, such as an easier learning curve, it is unclear if it has comparable diagnostic utility as electromagnetic navigational bronchoscopy.

METHODS

Robotic versus Electromagnetic bronchoscopy for pulmonary LesIon AssessmeNT (RELIANT) is an investigator-initiated, single-center, open label, noninferiority, cluster randomized controlled trial conducted in two operating rooms at Vanderbilt University Medical Center. Each operating room (OR) is assigned to either robotic-assisted or electromagnetic navigational bronchoscopy each morning, with each OR day considered one cluster. All patients undergoing diagnostic bronchoscopy for evaluation of a peripheral pulmonary lesion in one of the two operating rooms are eligible. Schedulers, patients, and proceduralists are blinded to daily group allocations until randomization is revealed for each operating room each morning. The primary endpoint is the diagnostic yield defined as the proportion of cases yielding lesional tissue. Secondary and safety endpoints include procedure duration and procedural complications. Enrolment began on March 6, 2023, and will continue until 202 clusters have been accrued, with expected enrolment of approximately 400 patients by the time of completion in March of 2024.

DISCUSSION

RELIANT is a pragmatic randomized controlled trial that will compare the diagnostic yield of the two most commonly used bronchoscopic approaches for sampling peripheral pulmonary lesions. This will be the first known cluster randomized pragmatic trial in the interventional pulmonology field and the first randomized controlled trial of robotic-assisted bronchoscopy.

TRIAL REGISTRATION

ClinicalTrials.gov registration (NCT05705544) on January 30, 2023.

The effect of combining different sampling tools on the performance of electromagnetic navigational bronchoscopy for the evaluation of peripheral lung lesions and factors associated with its diagnostic yield

BACKGROUND

We assessed the performance of Electromagnetic navigational bronchoscopy (ENB) as a standalone diagnostic technique and the performance of different sampling tools used during the procedure.

METHODS

We recruited 160 consecutive patients who underwent ENB for peripheral lung lesions (PLL) at a tertiary care centre. The diagnostic performance of ENB and sampling tools was assessed using a logistic regression model and a ROC-curve in which the dependent variable was diagnostic success. A multivariate model was built to predict diagnostic success before performing ENB to select the best candidates for the procedure.

RESULTS

Most patients with PLLs in the study were male (65%), with a mean age of 67.9 years. The yield was 66% when the most common techniques were used together as suction catheter + transbronchial biopsy forceps (TBBx) + bronchoalveolar lavage + bronchial washing (p < 0.001) and increased to 69% when transbronchial needle aspiration (TBNA) and cytology brush were added (p < 0.001). Adding diagnostic techniques such as TBBx and TBNA resulted in an increase in diagnostic performance, with a statistically significant trend (p = 0.002). The logistic model area-under the ROC-curve for diagnostic success during ENB was 0.83 (95% CI:0.75-0.90; p < 0.001), and a logit value ≥ 0.12 was associated with ≥ 50% probability of diagnostic success.

CONCLUSIONS

ENB, as a stand-alone diagnostic tool for the evaluation of PLLs when performed by experienced operators using a multi-modality technique, has a good diagnostic yield. The probability of having a diagnostic ENB could be assessed using the proposed model.

Diagnosis based on electromagnetic navigational bronchoscopy-guided biopsied peripheral lung lesions in a 10-year-old girl: A case report

BACKGROUND

Electromagnetic navigational bronchoscopy (ENB) is an emerging diagnostic tool that enables practitioners to biopsy peripheral lung tissues that were previously only accessible under computed tomography (CT) guidance. However, few studies have investigated ENB use in children. Here, we report a case of a 10-year-old girl with peripheral lung lesions who complained of a 7-d persistent fever. She was diagnosed with Streptococcus parasanguinis infection based on findings obtained using ENB-guided transbronchial lung biopsy (TBLB).

CASE SUMMARY

A 10-year-old girl presented with constitutional symptoms of cough and fever of 7 days’ duration. Chest CT scans detected peripheral lung lesions and no endobronchial lesions. TBLB performed under the guidance of an ENB Lungpro navigation system was safe, well-tolerated, and effective for biopsying peripheral lung lesions. Examination of biopsied samples indicated the patient had a pulmonary Streptococcus parasanguinis infection, which was treated with antibiotics instead of more invasive treatment interventions. The patient’s symptoms resolved after she received a 3-wk course of oral linezolid. Comparisons of pre-treatment and post-treatment CT scans revealed absorption of some lung lesions within 7 mo of hospital discharge.

CONCLUSION

ENB-guided TBLB biopsying of peripheral lung lesions in this child is a safe, well-tolerated, and effective alternative to conventional interventions.

Predictors of Success When Implementing an Electromagnetic Navigational Bronchoscopy Program

INTRODUCTION

With the advent of lung cancer screening, lung nodules are being discovered at an increasing rate. With improvements in transbronchial biopsy technology, it is important for thoracic surgeons to be involved with diagnostic procedures. The aim of this project is to relate the thoracic surgeon experience in implementing an electromagnetic navigational bronchoscopy (ENB) program at our institution and describe the factors that led to successful navigation (the ability to position a biopsy instrument in range for biopsy) and diagnostic biopsy of nodules.

METHODS

The thoracic surgery ENB program was initiated in 2014. A retrospective analysis of patients referred to thoracic surgery from 2014 to 2019 for lung nodule evaluation was performed. Patients who underwent ENB and biopsy were included. Recursive partitioning (CART) and multivariable regression analyses were used to identify predictors of successful navigation and biopsy.

RESULTS

There were 73 patients who underwent ENB evaluation of 91 nodules from 2014 to 2019. There was successful navigation in 75.8% of nodules, and on multivariable analysis, bronchus sign, lesion size, and pleural distance were significant predictors of successful navigation. Of the lesions that had successful navigation, 65.2% had a diagnostic biopsy. Based on CART analysis, positive bronchus sign and lesion size ≥ 1.3 cm were most predictive of obtaining a diagnostic biopsy with a probability of 0.75.

CONCLUSIONS

Nodule size, distance to the pleura, and bronchus size are independent variables of successful navigation when using ENB. However, of the lesions that were successfully reached, combined lesion size >1.3 cm and a positive bronchus sign were most predictive of obtaining a diagnostic biopsy. These factors should be considered when implementing an ENB program in a thoracic surgery practice.

High Accuracy of Digital Tomosynthesis-Guided Bronchoscopic Biopsy Confirmed by Intraprocedural Computed Tomography

BACKGROUND

Digital fluoroscopic tomosynthesis-guided electromagnetic navigational bronchoscopy (F-ENB) is a novel adjunct to ENB associated with higher diagnostic yield. The likelihood of F-ENB allowing accurate placement of a biopsy needle within a target remains unclear.

OBJECTIVE

This study intends to determine the accuracy of F-ENB as confirmed by cone-beam computed tomography (CBCT) scan.

METHODS

Patients undergoing CBCT-assisted ENB for lung nodule biopsy were prospectively enrolled. ENB was performed followed by digital tomosynthesis correction. Once optimal F-ENB alignment was achieved, and a needle was advanced into the expected location of the nodule followed by CBCT. The primary outcome was the percentage of "needle-in-lesion" hits, defined as needle tip within the nodule in 3 planes. Secondary outcomes were diagnostic yield, procedure and room time, complications, radiation, and distance between the needle tip and nodule.

RESULTS

Twenty-six patients with a total of 29 nodules were enrolled. Mean nodule size was 13 mm (±4 mm) in maximal axial dimension, 83% (n = 24) were located in the peripheral third of the chest, and 17% (n = 5) had a bronchus sign. F-ENB guidance resulted in needle-in-lesion in 21 of 29 nodules (72%). Mean needle tip-to-nodule distance for nonhits was 1.75 mm (±1.35 mm). There were no complications.

CONCLUSION

F-ENB resulted in a needle-in-lesion biopsy in greater than 70% of nodules despite features traditionally associated with poor diagnostic yield (size, absence of bronchus sign). Mean distance between needle tip and target for nonhits was less than 2 mm. These data suggest F-ENB alignment is accurate for small peripheral nodules.

Diagnostic yield of electromagnetic navigational bronchoscopy: A safety net community-based hospital experience in the United States

INTRODUCTION:

Electromagnetic navigational bronchoscopy (ENB) is an excellent tool to diagnose peripheral pulmonary nodules, especially in the setting of emphysema and pulmonary fibrosis. However, most of these procedures are done by interventional pulmonologists and academic tertiary centers under general anesthesia. Studies evaluating the diagnostic utility of this tool in safety-net community hospitals by pulmonologists not formally trained in this technology are lacking. The objective was to evaluate the diagnostic yield of ENB done in such a setting and its associated complications.

METHODS:

Retrospective chart review of consecutive ENB procedures over 5 years from 2014, since its inception in our institution-a safety-net community based hospital was performed. Multiple variables were analyzed to assess their impact on diagnostic yields.

RESULTS:

After exclusion criteria were applied, 72 patients with 76 procedures were eventually included within our study, with an overall 1-year diagnostic yield of 80.2%. Sensitivity for malignancy was 73% and negative predictive value of 65%. Primary lung cancer was the most common diagnosis obtained, followed by tuberculosis (TB). The overall complication rates were low, with only 1 patient (1.3%) requiring hospitalization due to pneumothorax needing tube thoracostomy. No deaths or respiratory failures were noted within the cohort. The only significant variable affecting diagnostic yield was forced expiratory volume in 1 s. The presence of emphysema did not affect diagnostic yield.

CONCLUSIONS:

ENB is safe and feasible with a high diagnostic success rate even when performed by pulmonologists not formally trained in interventional pulmonology in low resource settings under moderate sedation.

State of the Art: Robotic Bronchoscopy

Increased detection of lung nodules has led to trying to improve technologies for localization and/or tissue acquisition. Previous bronchoscopic techniques have limitations that have led to further advancements in technology. Robotic bronchoscopy has emerged as new technology for the localization, diagnosis, and potential treatment of lung nodules. The robotic bronchoscopic platform was developed to improve peripheral reach of lung nodules, provide direct continuous visualization of the periphery, and offer more precise control of the instrumentation. We review the progression of bronchoscopy, evolution to the robotic platform and its early outcomes, with considerations for future advancements.

Role of Computed Tomography-guided Biopsies in the Era of Electromagnetic Navigational Bronchoscopy: A Retrospective Study of Factors Predicting Diagnostic Yield in Electromagnetic Navigational Bronchoscopy and Computed Tomography Biopsies

Objectives:

Over 25% of the high-risk population screened for lung cancer have an abnormal computed tomography (CT) scan. Conventionally, these lesions have been biopsied with CT guidance with a high diagnostic yield. Electromagnetic navigational bronchoscopy (ENB) with transbronchial biopsy has emerged as a technology that improves the diagnostic sensitivity of conventional bronchoscopic biopsy. It has been used to biopsy lung lesions, due to the low risk of pneumothorax. It is, however, a new technology that is expensive and its role in the diagnosis of the solitary pulmonary nodule (SPN) is yet to be determined. The purpose of this study was to evaluate the diagnostic yield of CT-guided biopsy (CTB) following non-diagnostic ENB biopsy and identify characteristics of the lesion that predicts a low diagnostic yield with ENB, to ensure appropriate use of ENB in the evaluation of SPN.

Materials and Methods:

One hundred and thirty-five lung lesions were biopsied with ENB from January 2017 to August 2019. Biopsies were considered diagnostic if pathology confirmed malignancy or inflammation in the appropriate clinical and imaging setting. We evaluated lesions for several characteristics including size, lobe, and central/peripheral distribution. The diagnostic yield of CTB in patients who failed ENB biopsies was also evaluated. Logistic regression was used to identify factors likely to predict a non-diagnostic ENB biopsy.

Result:

Overall, ENB biopsies were performed in 135 patients with solitary lung lesions. ENB biopsies were diagnostic in 52% (70/135) of the patients. In 23 patients with solitary lung lesions, CTBs were performed following a non-diagnostic ENB biopsy. The CTBs were diagnostic in 87% of the patients (20/23). ENB biopsies of lesions <21.5 mm were non-diagnostic in 71% of cases (42/59); 14 of these patients with non-diagnostic ENB biopsies had CTBs, and 86% of them were diagnostic (12/14). ENB biopsies of lesions in the lower lobes were non- diagnostic in 59% of cases (35/59); 12 of these patients with non-diagnostic ENB biopsies had CTBs, and 83% were diagnostic (10/12). ENB biopsies of lesions in the outer 2/3 were non-diagnostic in 57% of cases (50/87); 21 of these patients with non-diagnostic ENB biopsies had CTBs, and 86% were diagnostic (18/21).

Conclusion:

CTBs have a high diagnostic yield even following non-diagnostic ENB biopsies. Lesions <21.5 mm, in the outer 2/3 of the lung, and in the lower lung have the lowest likelihood of a diagnostic yield with ENB biopsies. Although CTBs have a slightly higher pneumothorax rate, these lesions would be more successfully diagnosed with CTB as opposed to ENB biopsy, in the process expediting the diagnosis and saving valuable medical resources.

Improved respiratory motion tracking through a novel fiducial marker placement guidance system during electromagnetic navigational bronchoscopy (ENB)

Background

Stereotactic ablative radiotherapy (SABR) is a treatment option for patients with early stage non-small cell lung cancer (NSCLC) and recurrent or oligometastatic disease who are not surgical candidates. Due to the continuous motion of tumors within the lungs, implementing a strategy to track the target lesion is crucial. One method is to place fiducial markers which the robotic SABR system is able to track during treatment. However, placing these markers in a manner that maximizes tracking efficacy can be challenging. Using a novel fiducial placement guidance system (FPGS) during fiducial deployment may offer a way to improve the quantity of fiducials tracked by the robotic SABR system.

Method

This was an institutional, retrospective review identifying all patients who received robotic SABR for lung tumors from May 2015 until January 2017. The FPGS was instituted in May 2016. The median number of fiducials tracked and the rate of complication was compared between patients whose fiducials were placed using FPGS versus those that were not.

Results

A total of 128 patients with 147 treated lung lesions were identified. Of the lesions that utilized FPGS (n = 44), 28 had 2 tracked fiducials (63.6%), 14 had 3 (31.8%) and 2 had 4 (4.6%). Of the lesions treated without FPGS (n = 103), 5 had 1 tracked fiducial (4.9%), 91 had 2 (88.4%), 6 had 3 (5.8%), and 2 had 4 (1.9%). A significant improvement in the median number of fiducials tracked per fraction was observed for the lesions with fiducials placed using FPGS on Wilcoxon rank sum test (p < 0.001). The rate of complication was low and not statistically different between cohorts (p = 0.44).

Conclusions

The FPGS can be used during the deployment of fiducial markers and may increase the number of fiducials tracked.

Trial registration

An exemption for this retrospective review was granted by the East Carolina University IRB under UMCIRB 15-001726.

Use of electromagnetic navigational bronchoscopy in robotic pulmonary resection

Robotic resection of pulmonary lesions has become a more common approach in the field of thoracic surgery. The greatest drawback of robotic resection is the lack of tactile feedback as compared to open approaches, making identification of intrapulmonary lesion difficult. Electromagnetic navigational bronchoscopy (navibronch) enables pre-incisional marking of pulmonary lesions for intraoperative identification. We sought to determine how effective navibronch was in our institution's robotic cases. Thirty-one patients underwent robotically assisted resection of 35 lesions with the assistance of navibronch from 7/2014 to 9/2015. Retrospective demographic and operative data were collected on these patients, and statistical analysis was conducted using ANOVA means testing, Chi-square, and non-parametric tests. The average age in this patient population was 63.7 ± 13.5 years. Eight patients (25.8%) were male. Twenty-five (80.6%) of the patients had pathology involving one lobe, with six (19.4%) in two lobes. 34 of the resections (97.1%) resulted in dye being localized to the first specimen; 34 (97.1%) were found to have the target pathology in the initial specimen. Further resection was carried out in 22 (62.9%) cases, with the final resection resulting in a segment in 2 (5.7%) and a lobe in 14 (40.0%). The mean number of lung specimens collected was 1.94 ± 0.13. The mean number of tumors in each target resection was 1.46 ± 0.66 in final pathology. Malignancy was found in 19 (54.3%) of final specimens. There were no complications related to navibronch. Navibronch is an effective technique in the identification and localization of pulmonary lesions in robotically assisted lung resections.

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.

Electromagnetic Navigational Bronchoscopy for Peripheral Pulmonary Nodules

Electromagnetic navigational bronchoscopy is a useful addition to the array of modalities available to sample peripheral lung lesions. Its utility in diagnosing peripheral lesions has been steadily increasing since the Food and Drug Administration first approved it in 2004. The improvement can be attributed to continuous refinement in technology, increasing training and experience with the procedure, perhaps widespread availability of rapid onsite cytologic evaluation, and better patient selection. It may also be attributable to improvements of the technology and more available tools to perform biopsy of the peripheral lung.

Recent clinical innovations in thoracic surgery in Hong Kong

The concept of personalized medicine, which aims to provide patients with targeted therapies while greatly reducing surgical trauma, is gaining popularity among Asian clinicians. Single port video-assisted thoracic surgery (VATS) has rapidly gained popularity in Hong Kong for major lung resections, despite bringing new challenges such as interference between surgical instruments and insertion of the optical source through a single incision. Novel types of endocutters and thoracoscopes can help reduce the difficulties commonly encountered during single-port VATS. Our region has been the testing ground and has led the development of many of these innovations. Performing VATS, in particular single-port VATS in hybrid operating theatre helps to localise small pulmonary lesions with real-time images, thus increasing surgical accuracy and pushes the boundaries in treating subcentimeter diseases. Such approach may be assisted by use of electromagnetic navigational bronchoscopy in the same setting. In addition, sublobar resection can also be more individualised according to pathologic tumour subtype that require rapid intraoperative diagnostic test to guide appropriate surgical therapy. A focus on technology and innovation for large tumours that require chest wall resection and reconstructions have also been on going, with new materials and prostheses that may be tailored to each individual needs. The current paper reviews the literature pertaining to the above topics and discusses recent related innovations in Hong Kong, highlighting the study results and future perspectives.

Hybrid DynaCT-guided electromagnetic navigational bronchoscopic biopsy†

Electromagnetic navigational bronchoscopy-guided biopsy of small pulmonary nodules can be challenging. Navigational error of the system and movement of the biopsy tool during its deployment adversely affect biopsy success. Furthermore, conventional methods to confirm navigational success such as fluoroscopy and radial endobronchial ultrasound become less useful for the biopsy of small lesions. A hybrid operating theatre can provide unparalleled real-time imaging through DynaCT scan to guide and confirm successful navigation and biopsy of difficult-to-reach or small lesions. We describe our technique for DynaCT image-guided electromagnetic navigational bronchoscopic biopsy of a small pulmonary nodule in the hybrid operating theatre. The advantages, disadvantages and special considerations in adopting this approach are discussed.