Lung Nodule Evaluation Using Robotic-Assisted Bronchoscopy at a Veteran’s Affairs Hospital

The incidence of lung nodules has increased with improved diagnostic imaging and screening protocols. Despite improvements for diagnosing pulmonary nodules with technologies such as electromagnetic navigational bronchoscopy (ENB), several limitations still exist including adequate visualization, localization, and diagnostic yield. Robotic-assisted bronchoscopy with ENB has been introduced as a method to overcome these shortcomings. We describe our initial experience in evaluating lung nodules with robotic assisted bronchoscopy. We retrospectively reviewed data on the first 25 patients that underwent robotic-assisted bronchoscopy and biopsy. We analyzed success with localization, diagnostic yield, and post procedural morbidity. Diagnostic yield was 96% (24/25) with no periprocedural morbidity. The majority of nodules were malignant or atypical (76%) and were located in the right upper lobe. Diameter ranged between 0.8–6.9 cm (median size 1–2 cm). Seventy-five percent of patients underwent subsequent treatment for cancer based on these results, with 25% having continued surveillance. Robotic assisted bronchoscopy is safe and accurate. Studies with larger numbers will allow better understanding of the diagnostic yield and clinical utility of this approach in comparison to other diagnostic tools for lung nodules.

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

<b><i>Background:</i></b> 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. <b><i>Objective:</i></b> This study intends to determine the accuracy of F-ENB as confirmed by cone-beam computed tomography (CBCT) scan. <b><i>Methods:</i></b> 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. <b><i>Results:</i></b> Twenty-six patients with a total of 29 nodules were enrolled. Mean nodule size was 13 mm (±4 mm) in maximal axial dimension, 83% (<i>n</i> = 24) were located in the peripheral third of the chest, and 17% (<i>n</i> = 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. <b><i>Conclusion:</i></b> 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.

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.