Terunaga Inage

Elastography for Predicting and Localizing Nodal Metastases during Endobronchial Ultrasound

Background: Elastography is a relatively new technology that can generate images reflective of tissue stiffness (elasticity). Neoplastic tissue is usually stiffer than normal structures. Objectives: The aim of this study was to evaluate the feasibility and utility of elastography when combined with convex-probe endobronchial ultrasound (CP-EBUS) for predicting and localizing metastatic lymph nodes during endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA). Methods: Consecutive results of endobronchial elastography of lymph nodes performed using EBUS- TBNA were prospectively collected and retrospectively analyzed. Elastography images were acquired as JPEG images and also recorded as video clips. Stiff area ratios [(stiff areas as blue pixels) / (lymph node areas as region of interest pixels)] for each lymph node determined by elastography were collated with the results of pathological diagnosis. We also performed elastography of surgically resected lymph nodes and compared image findings with pathological sections. Results: We evaluated 49 lymph nodes in 21 patients by CP-EBUS. There were 16 metastatic nodes (10 lung cancer metastases and 6 metastases from extrathoracic malignancies). Mean stiff area ratios were significantly greater for metastatic lymph nodes (0.478) than for benign nodes (0.216; p = 0.0002). Using a cutoff value of 0.311 for stiff area ratios, the sensitivity and specificity for predicting metastatic disease were 0.81 and 0.85, respectively. The stiff area was histologically compatible with metastatic distribution in surgically resected lymph nodes. Conclusions: Endobronchial elastography is feasible for lymph nodes when combined with CP-EBUS. Stiff area ratios are useful for predicting metastatic lymph nodes, which may be an efficient guide for TBNA.

Endobronchial elastography in the evaluation of esophageal invasion

Because a primary tracheal tumor occasionally invades surrounding structures, such as the thyroid, esophagus, and great vessels, pretreatment evaluation is important for surgical planning. The usual imaging modalities for tracheal tumors include computed tomography (CT), magnetic resonance imaging, and endoscopic ultrasound (EUS). However, the resolving power of these modalities can be unsatisfactory because of the anatomy of this area. Although EUS was reported to be useful for evaluating malignant invasion of themediastinum, obtaining an imagewith a clear distinction between the border of a tumor and the surrounding tissue using EUS is difficult.

Evaluating vertebral artery dominancy before T4 lung cancer surgery requiring subclavian artery reconstruction

PurposesTo evaluate vertebral artery (VA) dominancy and the risk of brain infarction in T4 lung cancer patients with tumor invasion into the subclavian artery.MethodsWe reconstructed the subclavian artery in 10 patients with T4 non-small cell lung cancer. The histological stages were IIIA in eight patients and IIIB in two patients. We evaluated the VA dominancy by performing a four-vessel study preoperatively and investigated the relationship between the methods of VA treatment and postoperative brain complications, retrospectively.ResultsSeven patients had a superior sulcus tumor (SST) and three had direct invasion into the mediastinum. Based on the tumor location, a transmanublial approach was used in five patients and a posterolateral hook incision was used in the other five. All subclavian artery (SA) reconstructions were done using an artificial woven graft. Preoperative angiography of the VA revealed poor development of the contralateral side in two patients. One of these patients suffered a severe brain infarction on postoperative day 2, which proved fatal. In the other patient, the VA was connected to the left SA graft by a side-to-end anastomosis and there was no postoperative brain complication.ConclusionsPreoperative SA and VA angiography is mandatory for identifying the need for VA reconstruction in lung cancer patients with major arterial invasion.

Staging lung cancer: role of endobronchial ultrasound.

Accurate staging is the first step in the management of lung cancer. Nodal staging is quite important for physicians to be able to judge the primary operability of patients harboring no distant metastasis. For many years, mediastinoscopy has been considered a “gold standard” modality for nodal staging. Mediastinoscopy is known to be a highly sensitive procedure for mediastinal staging and has been performed worldwide, but is invasive. Because of this, clinicians have sought a less invasive modality for nodal staging. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive modality for diagnosis and staging of lung cancer. EBUS-TBNA is a needle biopsy procedure that has accessibility compatible with the reach of the convex-probe EBUS scope, so N1 nodes are also assessable. The diagnostic yield is similar to that of mediastinoscopy, and the core obtained by the dedicated needle biopsy can be used for histological assessment to determine the subtypes of lung cancer. The samples can also be used to test for various biomarkers using immunohistochemistry, polymerase chain reaction for DNA/complementary DNA, and in situ hybridization, and the technique is useful for selecting candidates for specific molecular-targeted therapeutic agents. According to the newly published American College of Chest Physicians guideline, EBUS-TBNA is now considered “the best first test” for nodal staging in patients with radiologically suspicious nodes. Appropriate training and thorough clinical experience is required to be able to perform correct nodal staging using this procedure.

Bronchial Embolization with an Endobronchial Watanabe Spigot for Broncho-Gastric Tube Fistula

Anastomotic failure of a gastric tube inserted for reconstruction following esophagectomy, which is relatively rare, causes pleural infection and persistent pleural irritation, leading to communication with the pulmonary parenchyma. Although several interventions have been reported to treat such broncho-gastric tube fistulas, refractory cases remain. We herein report the successful treatment by endoscopic bronchial occlusion with an endobronchial Watanabe spigot in 2 patients who suffered from the above complication.

Mini grasping basket forceps for endobronchial foreign body removal in pediatric patients

Appropriate device selection is crucial for endobronchial foreign body removal using a bronchoscope. In pediatric patients, bronchoscopy requires the use of a thin device due to the narrow access to the airway, limiting the range of useful endobronchial devices. We herein review our experience in endobronchial foreign body removal with a focus on the type of bronchoscope and the instruments used in comparison with the literature, and investigate the utility of mini grasping basket forceps (FG‐55D, Olympus®; and Zero Tip™, Airway Retrieval Basket, Boston Scientific).

Endobronchial embolization using a watanabe spigot for persistent air leakage

Background: Endobronchial embolization is an alternative strategy for the management of pneumothorax or empyema with persistent air leakage. The previous reports analyzed heterogeneous populations of patients, including patients with good performance status (PS, 0 or 1). However, the usefulness of Endobronchial embolization for managing persistent air leakage in patients with poor PS (3 or 4) is not well described. Methods: The aim of this study was to evaluate the feasibility of occlusion using an Endobronchial Watanabe Spigot (EWS) to treat persistent air leakage in patients with poor performance status. Charts of 10 consecutive patients who underwent endobronchial embolization using the EWS between March 2013 and April 2014 were retrospectively reviewed. Results: All patients had chronic pulmonary disease; 8 patients had parapneumonic empyema. The Eastern Cooperative Oncology Group performance status (PS) was 3 in 6 patients and 4 in 4 patients. EWS placement at the corresponding bronchus successfully reduced air leakage for all patients, and PS improved in 8 patients. The chest tube could be removed from 4 patients, and successful thoracoplasty was achieved in 3. The other 3 patients died while being managed for pyothorax by fenestration. There were no serious complications associated with EWS insertion.

Pathological diagnosis of pulmonary large cell neuroendocrine carcinoma by endobronchial ultrasound-guided transbronchial needle aspiration: Pulmonary LCNEC diagnosis by EBUS-TBNA

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a relatively rare subtype of lung malignancy. According to revised 2015 World Health Organization (WHO) criteria for the pathological diagnosis of LCNEC, neuroendocrine markers must be examined by immunohistochemistry. In this study, we reevaluated endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) samples of patients previously diagnosed with LCNEC using the revised WHO criteria.

Molecular Nodal Staging Using miRNA Expression in Lung Cancer Patients by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

Background: The limited negative predictive value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has often been discussed. Objective: The aim of this study was to identify a highly sensitive molecular biomarker for lymph node staging by EBUS-TBNA. Methods: Five microRNAs (miRNAs) (miR-200a, miR-200b, miR-200c, miR-141, and let-7e) were selected as biomarker candidates for the detection of nodal metastasis in a miRNA expression analysis. After having established a cutoff level of expression for each marker to differentiate malignant from benign lymph nodes among surgically dissected lymph nodes, the cutoff level was applied to snap-frozen EBUS-TBNA samples. Archived formalin-fixed paraffin- embedded (FFPE) samples rebiopsied by EBUS-TBNA after induction chemoradiotherapy were also analyzed. Results: The expression of all candidate miRNAs was significantly higher in metastatic lymph nodes than in benign ones (p < 0.05) among the surgical samples. miR-200c showed the highest diagnostic yield, with a sensitivity of 95.4% and a specificity of 100%. When the cutoff value for miR-200c was applied to the snap-frozen EBUS-TBNA samples, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 97.4, 81.8, 95.0, 90.0, and 94.0%, respectively. For restaging FFPE EBUS- TBNA samples, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 100, 60.0, 80.0, 100, and 84.6%, respectively. Among the restaged samples, 4 malignant lymph nodes were false negative by EBUS-TBNA, but they were accurately identified by miR-200c. Conclusions: miR-200c can be used as a highly sensitive molecular staging biomarker that will enhance nodal staging of lung cancer.

Specimen acquisition training with a new biosimulator in endobronchial ultrasound-guided transbronchial needle aspiration

Abstract Training for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has focused on the procedure itself; however, the techniques for obtaining adequate sample are also important for achieving a pathological diagnosis as well as for molecular testing. The aim of this study was to evaluate the feasibility and efficacy of a biosimulator for training subjects in adequate sample acquisition during EBUS-TBNA. A total of 19 bronchoscopists voluntarily participated in this study. A biosimulator (ArtiCHEST, HARADA Corporation, Tokyo, Japan) was used for the training. After a 10-minute briefing, the first pass was performed by pairs of trainees. The trainees then received a 30-minute lecture that focused on the acquisition of samples using EBUS-TBNA. The trainees next performed their second pass under the supervision of the trainers. Each participant obtained a cytological smear that was coded and evaluated for quantity as well as quality by an independent cytotechnologist. The trainees had an average of 5.9 years of bronchoscopy experience. With regard to the quantity evaluation, 9 (47.4%) subjects sampled a greater number of lymphocytes on the second pass than on the first, whereas 2 were better on the first pass, and the others sampled roughly the same amount both times. With regard to the quality assessment, 9 (47.4%) subjects obtained better quality samples on the second pass, whereas the quality of the first and second pass was deemed to be roughly the same for the remaining subjects. A biosimulator can be used to train doctors in specimen acquisition and evaluate their skills with sampling using EBUS-TBNA.