Pleural dye marking of lung nodules by electromagnetic navigation bronchoscopy

[The role of endoscopy in the management of peripheral pulmonary nodules, part 2: Treatment]

The management of peripheral lung nodules is challenging, requiring specialized skills and sophisticated technologies. The diagnosis now appears accessible to advanced endoscopy (see Part 1), which can also guide treatment of these nodules; this second part provides an overview of endoscopy techniques that can enhance surgical treatment through preoperative marking, and stereotactic radiotherapy treatment through fiduciary marker placement. Finally, we will discuss how, in the near future, these advanced endoscopic techniques will help to implement ablation strategy.

Endoscopic Technologies for Peripheral Pulmonary Lesions: From Diagnosis to Therapy

Peripheral pulmonary lesions (PPLs) are frequent incidental findings in subjects when performing chest radiographs or chest computed tomography (CT) scans. When a PPL is identified, it is necessary to proceed with a risk stratification based on the patient profile and the characteristics found on chest CT. In order to proceed with a diagnostic procedure, the first-line examination is often a bronchoscopy with tissue sampling. Many guidance technologies have recently been developed to facilitate PPLs sampling. Through bronchoscopy, it is currently possible to ascertain the PPL's benign or malignant nature, delaying the therapy's second phase with radical, supportive, or palliative intent. In this review, we describe all the new tools available: from the innovation of bronchoscopic instrumentation (e.g., ultrathin bronchoscopy and robotic bronchoscopy) to the advances in navigation technology (e.g., radial-probe endobronchial ultrasound, virtual navigation, electromagnetic navigation, shape-sensing navigation, cone-beam computed tomography). In addition, we summarize all the PPLs ablation techniques currently under experimentation. Interventional pulmonology may be a discipline aiming at adopting increasingly innovative and disruptive technologies.

NAVIGATE 24-Month Results: Electromagnetic navigation bronchoscopy for pulmonary lesions at 37 centers in Europe and the United States

INTRODUCTION

Electromagnetic navigation bronchoscopy (ENB) is a minimally invasive, image-guided approach to access lung lesions for biopsy or localization for treatment. However, no studies have reported prospective 24-month follow-up from a large, multinational, generalizable cohort. This study evaluated ENB safety, diagnostic yield, and usage patterns in an unrestricted, real-world observational design.

METHODS

The NAVIGATE single-arm, pragmatic cohort study (NCT02410837) enrolled subjects at 37 academic and community sites in 7 countries with prospective 24-month follow-up. Subjects underwent ENB using the superDimension navigation system versions 6.3 to 7.1. The prespecified primary endpoint was procedure-related pneumothorax requiring intervention or hospitalization.

RESULTS

A total of 1,388 subjects were enrolled for lung lesion biopsy (1,329; 95.7%), fiducial marker placement (272; 19.6%), dye marking (23; 1.7%), and/or lymph node biopsy (36; 2.6%). Concurrent endobronchial ultrasound-guided staging occurred in 456 subjects. General anesthesia (78.2% overall, 56.6% Europe, 81.4% US), radial endobronchial ultrasound (50.6%, 4.0%, 57.4%), fluoroscopy (85.0%, 41.7%, 91.0%), and rapid on-site evaluation use (61.7%, 17.3%, 68.5%) differed between regions. Pneumothorax and bronchopulmonary hemorrhage occurred in 4.7% and 2.7% of subjects, respectively (3.2% [primary endpoint] and 1.7% requiring intervention or hospitalization). Respiratory failure occurred in 0.6%. The diagnostic yield was 67.8% (range 61.9%-70.7%; 55.2% Europe, 69.8% US). Sensitivity for malignancy was 62.6%. Lung cancer clinical stage was I-II in 64.7% (55.3% Europe, 65.8% US).

CONCLUSIONS

Despite a heterogeneous cohort and regional differences in procedural techniques, ENB demonstrates low complications and a 67.8% diagnostic yield while allowing biopsy, staging, fiducial placement, and dye marking in a single procedure.

Preoperative electromagnetic navigation bronchoscopy-guided one-stage multiple-dye localization for resection of subsolid nodules: A single-center pilot study

Background

Electromagnetic navigation bronchoscopy (ENB)‐guided transbronchial dye marking and video‐assisted thoracoscopic surgery (VATS) is an emerging technique that enables successful resection of multiple small subsolid pulmonary nodules. The aim of this study was to evaluate the accuracy and safety of preoperative ENB‐guided transbronchial multiple dye localization for VATS resection of subsolid pulmonary nodules.

Methods

As a single‐center pilot study, we recruited patients with at least two small or subsolid pulmonary nodules. Multiple‐dye localization was performed by intraoperative ENB‐guided transbronchial injection of an indigo carmine dye. The patients underwent VATS for sublobar resection immediately after localization. The accuracy of ENB‐guided dye marking was checked.

Results

ENB‐guided one‐stage multiple dye localization was conducted for 18 pulmonary nodules in seven patients between September 2018 and December 2019. The mean diameter of the pulmonary nodules was 9.3 mm (range, 4–18) and the mean distance from the pleura to pulmonary nodule was 6 mm (range, 1–17 mm). ENB‐guided transbronchial multiple dye localization was successfully performed in 94.4% (17/18), and the accuracy of ENB‐guided dye marking was 88.2% (15/17). When two nodules were not seen in intraoperative fields, anatomical sublobar resection was performed. There was no conversion to thoracotomy and operative mortalities. Among the seven patients, only one patient showed mild intrabronchial bleeding but stopped spontaneously. The changes in lung function after multiple wedge resections (−1.6% to 24.8%) were tolerable level.

Conclusions

ENB‐guided one‐stage transbronchial dye localization showed accurate and safe intraoperative identification of multiple subsolid pulmonary nodules. A large scale prospective clinical study is warranted.

Electromagnetic navigation bronchoscopy localization of lung nodules for thoracoscopic resection

Background

Thoracoscopic localization of small peripheral pulmonary nodules is a concern. Failure can lead to larger parenchymal resection or conversion to thoracotomy. This study evaluates our experience in preoperative electromagnetic navigation bronchoscopy-guided localization of small peripheral lung lesions.

Methods

From January 2017 to March 2020 clinical, radiographic, surgical, and pathological data of patients who underwent electromagnetic navigation bronchoscopy (ENB)-guided methylene blue pleural marking of highly suspected pulmonary lesions before a full thoracoscopic resection were evaluated. Localization was performed for solid or mixed subpleural nodules measuring <10 mm, solid nodules measuring <20 mm located at more than 1 cm from the pleura and any pure ground glass opacity. Successful localization was defined as successful identification and thoracoscopic resection of target lesions.

Results

Forty-eight patients were included: 30 solid nodules (63%), 12 pure GGO (25%) and 6 mixed (13%). The median largest diameter at CT-scan was 11 mm (IQR, 9-14 mm) while the median distance from the pleural surface was 12 mm (IQR, 6-16 mm). The median ENB length was 25 min (19-33 min). Localization procedure was successful in 45 cases (94%). No procedural-related complications were reported.

Conclusions

ENB is a safe and accurate preoperative procedure to localize small lung peripheral lesions. The high successful rate, the absence of related complications, the possibility of performing the procedure in the same operating room with a single general anesthesia, make ENB-guided dye marking an advantageous tool for thoracoscopic pulmonary resection.

Optimizing Diagnostic and Staging Pathways for Suspected Lung Cancer: A Decision Analysis

BACKGROUND

The optimal diagnostic and staging strategy for patients with suspected lung cancer is not known.

RESEARCH QUESTION

What diagnostic and staging strategies are most cost-effective for lung cancer?

STUDY DESIGN AND METHODS

A decision model was developed by using a hypothetical patient with a high probability of lung cancer. Sixteen unique permutations of bronchoscopy with fluoroscopy, radial endobronchial ultrasound, electromagnetic navigation, convex endobronchial ultrasound with or without rapid-onsite evaluation (ROSE), CT-guided biopsy (CTBx), and surgery were evaluated. Outcomes included cost, complications, mortality, time to complete the evaluation, rate of undetected N2-3 disease at surgery, incremental cost-complication ratio, and willingness-to-pay thresholds. Sensitivity analyses were performed on primary outcomes.

RESULTS

For a peripheral lung lesion and radiographic N0 disease, the best bronchoscopy strategy costs $1,694 more than the best CTBx strategy but resulted in fewer complications (risk difference, 14%). The additional cost of bronchoscopy to avoid one complication from a CTBx strategy was $12,037. The cost and cumulative complications of bronchoscopy strategies increased compared with CTBx strategies for small lesions. The cost and cumulative complications of bronchoscopy strategies decreased compared with CTBx strategies when a bronchus sign was present, but bronchoscopy remained more costly overall. For a central lesion and/or radiographic N1-3 disease, convex endobronchial ultrasound with ROSE followed by lung biopsy with incremental cost-effectiveness ratio, if required, was more cost-effective than any CTBx strategy across all outcomes. Strategies with ROSE were always more cost-effective than those without, irrespective of scenario. Trade-offs also exist between different bronchoscopy strategies, and optimal choices depend on the value placed on individual outcomes and willingness-to-pay.

INTERPRETATION

The most cost-effective strategies depend on nodal stage, lesion location, type of peripheral bronchoscopic biopsy, and the use of ROSE. For most clinical scenarios, many strategies can be eliminated, and trade-offs between the remaining competitive strategies can be quantified.

The Impact of Biopsy Tool Choice and Rapid On-Site Evaluation on Diagnostic Accuracy for Malignant Lesions in the Prospective: Multicenter NAVIGATE Study

BACKGROUND

The diagnostic yield of electromagnetic navigation bronchoscopy (ENB) is impacted by biopsy tool strategy and rapid on-site evaluation (ROSE) use. This analysis evaluates usage patterns, accuracy, and safety of tool strategy and ROSE in a multicenter study.

METHODS

NAVIGATE (NCT02410837) evaluates ENB using the superDimension navigation system (versions 6.3 to 7.1). The 1-year analysis included 1215 prospectively enrolled subjects at 29 United States sites. Included herein are 416 subjects who underwent ENB-aided biopsy of a single lung lesion positive for malignancy at 1 year. Use of a restricted number of tools (only biopsy forceps, standard cytology brush, and/or bronchoalveolar lavage) was compared with an extensive multimodal strategy (biopsy forceps, cytology brush, aspirating needle, triple needle cytology brush, needle-tipped cytology brush, core biopsy system, and bronchoalveolar lavage).

RESULTS

Of malignant cases, 86.8% (361/416) of true positive diagnoses were obtained using extensive multimodal strategies. ROSE was used in 300/416 cases. The finding of malignancy by ROSE reduced the total number of tools used. A malignant ROSE call was obtained in 71% (212/300), most (88.7%; 188/212) by the first tool used (49.5% with aspirating needle, 20.2% with cytology brush, 17.0% with forceps). True positive rates were highest for the biopsy forceps (86.9%) and aspirating needle (86.6%). Use of extensive tool strategies did not increase the rates of pneumothorax (5.5% restricted, 2.8% extensive) or bronchopulmonary hemorrhage (3.6% restricted, 1.1% extensive).

CONCLUSION

These results suggest that extensive biopsy tool strategies, including the aspirating needle, may provide higher true positive rates for detecting lung cancer without increasing complications.

Electromagnetic Navigation Bronchoscopy-Guided Dye Marking for Localization of Pulmonary Nodules

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB)-guided dye marking is a useful localization modality for small pulmonary nodules. The purpose of this study was to evaluate the efficacy and safety of intraoperative full virtual ENB-guided dye marking.

METHODS

Patients who underwent full virtual ENB-guided dye marking without adjunct intraoperative imaging (fluoroscopy or cone beam computed tomography) for small pulmonary nodules were investigated retrospectively. Efficacy was evaluated on the basis of the success rates of dye marking (visible dye mark) and nodule localization, and safety was evaluated on the basis of the rate of ENB-related complications.

RESULTS

ENB-guided dye marking was performed on 164 nodules in 134 patients. Twenty-seven (20.1%) patients had multiple nodules. The total number of dye-marking attempts was 241, and the mean number of markings per nodule was 1.5±0.7. The mean ENB procedure duration was 30±15.1 min. No ENB-related complications were observed. The success rate of dye marking was 86.7% (209/241), and that of localization was 94.5% (155/164). Among 63 nodules with multiple dye-marking attempts, 62 (98.4%) were successfully localized. In 101 nodules with a single dye-marking attempt, 88 (87.1%) were localized with the visceral pleural dye mark. Additionally, 6 (5.9%) nodules could be localized with the needle hole on the visceral pleura. The number of dye-marking attempts was a significant factor in the success of localization (1.5±0.7 versus 1.1±0.3, p=0.01).

CONCLUSIONS

Full virtual ENB-guided dye marking was effective and safe for the localization of small pulmonary nodules. A multiple dye-marking strategy is recommended to achieve a high success rate.

A narrative review of invasive diagnostics and treatment of early lung cancer

The diagnosis and treatment of early-stage lung cancer remains a clinical challenge. The broadening implementation of lung cancer screening has resulted in positive findings in numerous patients that are mostly non-malignant. Many other patients have indeterminate nodules that are difficult to assess through simple observation. The critical interpretation of such screening results remains a challenge for radiologists and multidisciplinary teams involved in screening for lung cancer. The evaluation and diagnosis of each participant suspected for malignancy should be based on the basic clinical principles such as a carefully collected medical history, physical examination, and detailed analysis of all imaging tests performed. Indeed, the decision to go ahead with more invasive diagnostics requires consideration of the both the risks and benefits, with reflection upon the complete clinical and radiological picture. Although transthoracic needle aspiration biopsy remains the first-choice method of diagnosis, several newer technologies have slowly begun to emerge as potential replacements. The guiding strategy for method selection is to choose the least harmful approach that offers the most relevant potential insights. Transthoracic biopsy is an effective method that allows the collection of cytological and tissue material from small, peripheral tumors, but it carries a moderate risk of complications. Bronchofiberoscopy, especially in combination with electromagnetic navigation, fluoroscopy or radial EBUS, also allows effective diagnosis of the peripheral pulmonary nodules. One of the most important diagnostic methods is the EBUS examination, which allows determining of staging in addition to diagnosis. Anatomical lung lobe resection and lymphadenectomy or sampling of the hilar and mediastinal lymph nodes is currently the treatment of choice for patients with stage I and II non-small cell lung cancer (NSCLC), but sublobar resections are recommended when a patient has limited pulmonary function or other significant comorbidities. Notably, several studies have highlighted the potential utility of more limited resections in small malignant lesions less than 2cm in diameter, with pure AIS histology, when more than 50% of the diameter of pulmonary nodule has ground-glass opacity (GGO) attenuation on CT, or long volume doubling time (VDT). Videothoracoscopy is the preferred surgical approach for resection of early-stage lung cancer. Patients who are not candidates for surgery or do not agree to surgery can be offered radical radiotherapy. Stereotactic body radiation therapy (SBRT) is a type of radical radiotherapy with proven effectiveness, a high rate of local control and an acceptable risk of the development of later complications. Future trials are expected to define the role of SBRT in the treatment of early lung cancer in healthy subjects.

Precise sublobar lung resection for small pulmonary nodules: localization and beyond

Early-stage primary lung cancer is increasingly detected by computed tomographic (CT) screening and the radicality of sublobar lung resection (wedge resection and segmentectomy) has been suggested. However, identification of a tumor intraoperatively becomes more difficult, the earlier a nodule is detected. A solution to this challenge is localization techniques. There are many techniques to localize small pulmonary nodules, including that replacing surgeon's tactile sensation, visualizing the tumor using ultrasound, and various types of lung markings that are placed percutaneously under CT guidance or bronchoscopically. The most commonly used technique is CT-guided placement of a hookwire, but there are concerns about potentially fatal air embolism. Bronchoscopic localization, especially using electromagnetic navigation bronchoscopy with or without intraoperative cone-beam CT imaging, has been increasingly reported. Beyond localization, the concept of lung "mapping" is emerging. In sublobar lung resection, in addition to localization of the targeted tumor, acquisition of sufficient resection margins is critical to prevent local recurrence. Virtual-assisted lung mapping (VAL-MAP) has evolved from bronchoscopic dye localization, but by placing multiple dye marks, it provides two-dimensional geometric information on the lung. Moreover, to ensure deep resection margins, the newly developed technique of VAL-MAP 2.0 combining dye marks and intrabronchial placement of a microcoil enables three-dimensional lung mapping. This allows for intraoperative navigation of lung resection under a fluoroscope. Development of this field, such as using a new technology of augmented reality, will further enhance the accuracy and convenience of lung resection in the near future.

Navigation Bronchoscopy

With the advent of lung cancer screening, and the increasingly frequent use of computed tomography (CT) scanning for investigating non-pulmonary pathology (for example CT coronary angiogram), the number of pulmonary nodules requiring further investigation has risen significantly. Most of these nodules are found in the lung periphery, which presents challenges to biopsy, and many centers rely on trans-thoracic needle biopsy performed under image guidance by radiologists. However, the desire to minimize complications is driving the development of increasingly accurate navigation bronchoscopy platforms, something that will be crucial in the new era of bronchoscopic therapeutics for lung cancer. This review describes these platforms, summarizes the current evidence for their use, and takes a look at future developments.