Characterizing the accuracy of robotic bronchoscopy in localization & targeting of small pulmonary lesions.

PURPOSE: Considering the recent implementation of lung cancer screening guidelines, it is crucial that small pulmonary nodules are accurately diagnosed. There is a significant need for quick, precise, and minimally invasive biopsy methods, especially for patients with small lung lesions in the outer periphery. Robotic bronchoscopy (RB) has recently emerged as a novel solution. The purpose of this study was to evaluate the accuracy of RB compared to the existing standard, electromagnetic navigational bronchoscopy (EM-NB). METHODS: A prospective, single-blinded, and randomized-controlled study was performed to compare the accuracy of RB to EM-NB in localizing and targeting pulmonary lesions in a porcine lung model. Four operators were tasked with navigating to four pulmonary targets in the outer periphery of a porcine lung, to which they were blinded, using both the RB and EM-NB systems. The dependent variable was accuracy. Accuracy was measured as a rate of success in lesion localization and targeting, the distance from the center of the pulmonary target, and by anatomic location. The independent variable was the navigation system, RB was compared to EM-NB using 1:1 randomization. RESULTS: Of 75 attempts, 72 were successful in lesion localization and 60 were successful in lesion targeting. The success rate for lesion localization was 100% with RB and 91% with EM- NB. The success rate for lesion targeting was 93% with RB and 80% for EM-NB. RB demonstrated superior accuracy in reaching the distance from the center of the lesion, at 0.62 mm compared to EM-NB at 1.28 mm (p = 0.001). Accuracy was improved using RB compared to EM- NB for lesions in the LLL (p = 0.025), LUL (p < 0.001), and RUL (p < 0.001). CONCLUSION: Our findings support RB as a more accurate method of navigating and localizing small peripheral pulmonary targets when compared to standard EM-NB in a porcine lung model. This may be attributed to the ability of RB to reduce substantial tissue displacement seen with standard EM-NB navigation. As the development and application of RB advances, so will the ability to accurately diagnose small peripheral lung cancer nodules, providing patients with early-stage lung cancer the best possible outcomes.

Percutaneous Electromagnetic Transthoracic Nodule Localization for Ground Glass Nodules.

BACKGROUND: A recent increase in the incidental detection of ground glass nodules (GGNs) has created a need for improved diagnostic accuracy in screening for malignancies. However, surgical diagnosis remains challenging, especially via video-assisted thoracoscopic surgery (VATS). Herein, we present the efficacy of a novel electrical navigation system for perioperative percutaneous transthoracic nodule localization. METHODS: Eighteen patients with GGNs who underwent electromagnetic navigated percutaneous transthoracic needle localization (ETTNL), followed by 1-stage diagnostic wedge resections via VATS between January and December 2020, were included in the analysis. Data on patient characteristics, nodules, procedures, and pathological diagnoses were collected and retrospectively reviewed. RESULTS: Of the 18 nodules, 17 were successfully localized. Nine nodules were pure GGNs, and the remaining 9 were part-solid GGNs. The median nodule size was 9.0 mm (range, 4.0-20.0 mm); and the median depth from the visceral pleura was 5.2 mm (range, 0.0-14.4 mm). The median procedure time was 10 minutes (range, 7-20 minutes). The final pathologic results showed benign lesions in 3 cases and malignant lesions in 15 cases. CONCLUSION: Perioperative ETTNL appears to be an effective method for the localization of GGNs, providing guidance for a 1-stage VATS procedure.

Electromagnetic bronchoscopy guided microwave ablation for early stage lung cancer presenting as ground glass nodule.

BACKGROUND: Patients with early-stage lung cancer are sometimes medically inoperable, and for patients with multiple primary lung cancers, surgical resection alone sometimes proves to be impractical. Local treatments like microwave ablation (MWA) are investigational alternatives for these patients. Most reported MWA procedures for lung cancers are performed percutaneously under CT guidance. MWA navigated by electromagnetic bronchoscopy (ENB) has been limitedly studied. In this study, we aimed to evaluate the safety and feasibility of MWA under ENB guidance in patients with inoperable early-stage lung cancers or multiple primary lung cancers which cannot be completely resected. METHODS: From June 2019 to December 2020, preliminary attempts of ENB-guided MWA were made in five medically inoperable patients with a single early-stage lung cancer and ten patients with multiple primary lung cancers which were difficult to resect at the same time. For patients with concomitant pulmonary nodules which needed surgical resection, thoracoscopic resections were performed following ENB-guided MWA. The safety, feasibility, and technique effectiveness of treatments were evaluated. RESULTS: ENB-guided MWA for 15 ground glass nodules (GGNs) in 15 patients was completed in accordance with the planned protocol. Biopsy of 13 GGNs showed malignancy. Five patients received simple ENB-guided MWA without simultaneous surgical resection and ten patients received simultaneous surgical resection for 13 concomitant pulmonary nodules. CT scan by the first postoperative week showed technique effectiveness of ablation for 11 nodules indicated for MWA. Four patients had mild complications after the procedure and recovered shortly after treatment. CONCLUSIONS: For medically inoperable patients with a single GGN manifesting early-stage lung cancer and patients with multiple primary early-stage lung cancers which cannot be resected at the same time, ENB-guided MWA might be a safe and feasible alternative local treatment, whether combined with surgical resection or not. However, large, prospective, randomized, multicenter studies are needed to confirm its role in the treatment of early-stage lung cancer.

Navigational transbronchial needle aspiration, percutaneous needle aspiration and its future.

Peripheral lung nodule evaluation represents a clinical challenge. Given that many nodules will be incidentally found with lung cancer screening following the publication of the National Lung Screening Trial (NLST), the goal is to find an accurate, safe and minimally-invasive diagnostic modality to biopsy the concerning lesions. Unfortunately, conventional bronchoscopic techniques provide a poor diagnostic yield of 18-62%. In recent years advances in technology have led to the introduction of electromagnetic navigational bronchoscopy (ENB) as a tool to guide sampling of peripheral lung nodules. The same principle has also recently been expanded and applied to the transthoracic needle biopsy, referred to as electromagnetic transthoracic needle aspiration (E-TTNA). An improved diagnostic yield has afforded this technology a recommendation by the 2013 3(rd) Edition ACCP Guidelines for the Diagnosis and Management of Lung Cancer which state that "in patients with peripheral lung lesions difficult to reach with conventional bronchoscopy, ENB is recommended if the equipment and the expertise are available (Grade 1C)". In this review we will discuss the technology, devices that are available, techniques and protocols, diagnostic yield, safety, cost effectiveness and more.

Electromagnetic navigational bronchoscopy.

Despite advances in technology and treatment options, lung cancer remains a deadly disease. National screening programs are being instituted in an attempt to discover lung cancer in high-risk individuals at an earlier stage. Such screening programs invariably discover small peripheral nodules that previously would not have been clinically apparent; the management of such lesions can be challenging. Current diagnostic options such as percutaneous biopsy are effective; however, they are hindered by their risk of morbidity such as pneumothorax. Electromagnetic bronchoscopy (ENB) is an emerging technology that allows the practitioner the ability to both sample and treat small peripheral pulmonary lesions. In experienced centers, ENB provides high rates of diagnostic yield for small lesions and a complication rate significantly lower than that of more conventional diagnostic modalities. Although there are current barriers to its widespread utilization (cost, specialized imaging, technical training), these obstacles will handled similarly to any other emerging technology and will likely not be long-term impediments to its use.