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SC19.01 Diagnosis of Lung Cancer: Multimodal Devices for Peripheral Pulmonary Lesions
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SC19.01 Diagnosis of Lung Cancer: Multimodal Devices for Peripheral Pulmonary Lesions Noriaki Kurimoto Kanagawa Prefecture/Japan When bronchoscopy is performed for peripheral pulmonary lesions (PPLs), a radial ultrasonic probe can be inserted from the working channel of the bronchoscope to reach the PPL1. We began using this technique of endobronchial ultrasonography (EBUS) in 1994. EBUS using a guide sheath (GS) also began in 19962. We would like to explain the technique and advantages of diagnosing PPLs using EBUS, GS, Navigation, and etc. Radial ultrasonic miniature-probe: A radial probe emits US while being rotated 360 ; the reflected US waveform is rendered as an image. The radial probe scans from the bronchial lumen to provide a short-axis image of the bronchial and para-bronchial tissue. Analyzing the internal structure of peripheral pulmonary lesions with a radial mini-probe: EBUS imaging before surgery has been compared with histopathologic findings of surgically resected tissue to determine the internal structures of PPLs that can be depicted by EBUS3. PPLs can be classified as heterogeneous or homogeneous based on irregularities in brightness within lesions seen on EBUS. Internal structures within peripheral lesions that can be identified by EBUS include patent blood vessels, patent bronchi, hemorrhage, calcification, dilated bronchi, necrosis, and small amounts of air in alveoli. EBUS using a guide sheath (EBUS-GS)1,2: The GScovered probe is advanced to the PPL, then after confirmation by EBUS that the lesion has been reached, the probe is removed before inserting the brush and biopsy forceps through the GS that is held in place in the lesion. This technique enables cytology and biopsy to be performed several times with minimal risk of bleeding. Insertion of the bronchoscope (saline immersion technique): After observing the bronchial lumen, the bronchoscope should be advanced while visualizing the branches to the bronchus near the peripheral lesion. Upon reaching a position where further advancement is not possible, flushing of 1-ml saline (total 5-10 ml) several times is performed through the working channel of the bronchoscope; this is done to fill the bronchus, remove any sputum, and visualize the lumen. The GScovered probe is then inserted from the working channel into the bronchus. In cases of ground glass nodule (GGN),
Journal of Thoracic Oncology
Vol. 12 No. 1S
we do not perform the saline immersion technique. Because the saline immersion technique will occur EBUS images of hyperechoic points which resemble EBUS image of GGN. EBUS visualization: The operator advances the US probe from the working channel of the 4-mm bronchoscope towards the periphery and stops when some resistance is felt. The duration of X-ray fluoroscopy should be limited as much as possible; also, an iris of the fluoroscopy machine should be used for fluoroscopy. Scanning while pulling back the probe from the distal site to the proximal site reduces strain on the probe and provides clear EBUS images. We have reported that EBUS imaging of PPLs can be used to diagnose and assess the degree of differentiation between benign and malignant lesions3. PPLs are classified as type I if the internal echoes are homogeneous, type III if the internal echoes are heterogeneous, and type II if there are mainly hyperechoic lines and dots near the probe. About 92% of type I lesions were benign, whereas 99% of type II and type III lesions were malignant. The positional relationship between the probe and a PPL is classified as “within” (probe placement within a lesion), when the 360 area around the probe is entirely surrounded by the lesion; and “adjacent to” (probe is in contact with a lesion) when a lesion is depicted, but the 360 area around the probe is not entirely surrounded by the lesion. Higher diagnostic yields have also been reported for lesions with a positive bronchus sign on computed tomography. Minezawa et al.4 reported that the CT bronchus sign was a significant predictive factor for successful bronchoscopic diagnosis in the multivariate analysis. We believe that bronchoscopists should trace the accurate bronchus leading to the PPL on CT axial images. When the lesion located in the middle lobe, the lingular segment, or bilateral lower lobes, we inverse CT axial images right to left, or left to right for watching the bronchus from the cranial site. When the lesion located in the right upper lobe, we rotate CT axial images counterclockwise 90 degrees. When the lesion located in the left superior segment, we rotate CT axial images clockwise 90 degrees. While tracing the bronchus on CT images, we could draw the illustration of the bronchus leading to PPLs. We usually use virtual bronchoscopic navigation (VBN) and compare the hand-written illustration of the bronchus leading to PPLs. Asano et al.5 reported that the diagnostic yield by EBUS-GS and VBN was between 63.3 and 84.4% in reports on VBN for PPLs searched in PubMed as of November 2013. When the ultrasonic probe advanced to the different bronchus a little far from the target lesion, EBUS image is invisible. In this case, we should change the direction of the tip of the bronchoscope using the up and down lever of the
January 2017
bronchoscope under fluoroscopy. We select the direction of the tip of the bronchoscope for facing the target lesion, and pull back and push the probe/GS for trying to insert the target lesion. When the ultrasonic probe advanced to the bronchus adjacent to the target lesion, EBUS image is called as “adjacent to.” In this case, we could change the direction of the tip of the bronchoscope using the up and down lever of the bronchoscope under the EBUS image. We use the up or down lever of the bronchoscope for changing the position of the probe and GS (probe/GS) to be close to the target lesion on EBUS image. Then we keep the same angle of the tip of the bronchoscope, and pull back and push the probe/GS for trying to insert the target lesion. 6) Cytology and tissue biopsy from the guide sheath The GS tip is placed within or adjacent to the PPL before passing the brush and biopsy forceps through the GS. References: 1. Kurimoto N, Fielding D, Musani A. Endobronchial Ultrasonography. 2011, Willy Blackwell. 2. Kurimoto N, Miyazawa T, Okimasa S, Maeda A, Oiwa H, Miyazu Y, Murayama M. Endobronchial ultrasonography using a guide sheath increases the ability to diagnose peripheral pulmonary lesions endoscopically. CHEST 2004; 126: 959-65. 3. Kurimoto N, Murayama M, Yoshioka S, Nishisaka T. Analysis of the internal structure of peripheral pulmonary lesions using endobronchial ultrasonography. CHEST 2002; 122: 1887-94. 4. Minezawa T, Okamura T, Yatsuya H, et al. Bronchus sign on thinsection computed tomography is a powerful predictive factor for successful transbronchial biopsy using endobronchial ultrasound with a guide sheath for small peripheral lung lesions: a retrospective observational study. BMC Med Imaging. 2015 21; 15:21. 5. Asano F, Eberhardt R, Herth F. Virtual Bronchoscopic Navigation for Peripheral Pulmonary Lesions. Respiration 2014; 88: 430-440. Keywords: bronchoscopy, peripheral pulmonary lesion, guide sheath, EBUS
SC19.02 Invasive Staging of Lung Cancer: EBUS, EUS and Beyond Kazuhiro Yasufuku Division of Thoracic Surgery, Toronto General Hospital, Univeristy of Toronto, Toronto/ ON/Canada Despite the advances in surgical treatment and multimodality treatment, lung cancer is still the leading cause of death from malignant disease worldwide. Accurate staging is important not only to determine the prognosis
Abstracts
S121
but also to decide the most suitable treatment plan. During the staging process of non-small cell lung cancer (NSCLC), mediastinal lymph node staging is one of the most important factors that affect the patient outcome. Non-invasive staging such as computed tomography (CT) and positron emission tomography (PET) indicate size and metabolic activity, respectively. However imaging alone is inaccurate and therefore tissue sampling is the preferred and most reliable. Surgical staging by mediastinoscopy has been the gold standard for mediastinal lymph node staging but requires general anesthesia and complications cannot be ignored. Endoscopic ultrasound techniques provide a minimally invasive alternative for surgical staging. The current available endoscopic ultrasound techniques for mediastinal staging include transesophageal endoscopic ultrasound guided fine needle aspiration (EUS-FNA) and endobronchial ultrasound guided transbronchial needle aspiration (EBUSTBNA). Both procedures can be performed in an outpatient setting under local anesthesia. EUS-FNA is a sensitive and safe method of evaluating the inferior mediastinal nodes (stations 7, 8, and 9) and some parts of the anterior mediastinal nodes if the lymph nodes are accessible from the esophagus. However, in spite of the strength of EUS-FNA for evaluating the inferior mediastinal nodes, its ability to evaluate lesions anterior to the trachea is limited. On the other hand, EBUS-TBNA has reach to the paratracheal and subcarinal (stations 2R, 2L, 4R, 4L, 7), as well as the N1 lymph nodes (stations 10, 11, 12). In experienced hands, EBUS can be used through the esophagus for a EUS-like approach to the inferior mediastinal lymph nodes. Thus, EUS-FNA and EBUSTBNA are complementary methods for lymph node staging in lung cancer and most of the mediastinum and the hilum can be evaluated with these endoscopic procedures. Aortic nodes (stations 5 and 6) are exceptions and must be evaluated by surgical methods (anterior mediastinotomy, VATS, thoracotomy). Based on the current evidence, EBUS-TBNA and EUS-FNA presents a minimally invasive endoscopic procedure as an alternative to mediastinoscopy for mediastinal staging of NSCLC with discrete N2 or N3 lymph node enlargement, provided negative results are confirmed by surgical staging. EBUS-TBNA can access all lymph nodes accessible by mediastinoscopy as well as hilar (N1) lymph nodes. EUSFNA has access to the inferior mediastinal lymph nodes not accessible by mediastinoscopy. EBUS-TBNA and/or EUS-FNA have in fact replaced mediastinoscopy in many patients with diffuse mediastinal adenopathy, where a simple tissue diagnosis is required to determine treatment. When combined the techniques offer safe and accurate assessment of mediastinum, with accuracy surpassing that of the pervious gold standard e cervical mediastinoscopy. EBUS-TBNA and/or EUS-FNA can also
SC19.01 Diagnosis of Lung Cancer: Multimodal Devices for Peripheral Pulmonary Lesions Noriaki Kurimoto Kanagawa Prefecture/Japan When bronchoscopy is performed for peripheral pulmonary lesions (PPLs), a radial ultrasonic probe can be inserted from the working channel of the bronchoscope to reach the PPL1. We began using this technique of endobronchial ultrasonography (EBUS) in 1994. EBUS using a guide sheath (GS) also began in 19962. We would like to explain the technique and advantages of diagnosing PPLs using EBUS, GS, Navigation, and etc. Radial ultrasonic miniature-probe: A radial probe emits US while being rotated 360 ; the reflected US waveform is rendered as an image. The radial probe scans from the bronchial lumen to provide a short-axis image of the bronchial and para-bronchial tissue. Analyzing the internal structure of peripheral pulmonary lesions with a radial mini-probe: EBUS imaging before surgery has been compared with histopathologic findings of surgically resected tissue to determine the internal structures of PPLs that can be depicted by EBUS3. PPLs can be classified as heterogeneous or homogeneous based on irregularities in brightness within lesions seen on EBUS. Internal structures within peripheral lesions that can be identified by EBUS include patent blood vessels, patent bronchi, hemorrhage, calcification, dilated bronchi, necrosis, and small amounts of air in alveoli. EBUS using a guide sheath (EBUS-GS)1,2: The GScovered probe is advanced to the PPL, then after confirmation by EBUS that the lesion has been reached, the probe is removed before inserting the brush and biopsy forceps through the GS that is held in place in the lesion. This technique enables cytology and biopsy to be performed several times with minimal risk of bleeding. Insertion of the bronchoscope (saline immersion technique): After observing the bronchial lumen, the bronchoscope should be advanced while visualizing the branches to the bronchus near the peripheral lesion. Upon reaching a position where further advancement is not possible, flushing of 1-ml saline (total 5-10 ml) several times is performed through the working channel of the bronchoscope; this is done to fill the bronchus, remove any sputum, and visualize the lumen. The GScovered probe is then inserted from the working channel into the bronchus. In cases of ground glass nodule (GGN),
Journal of Thoracic Oncology
Vol. 12 No. 1S
we do not perform the saline immersion technique. Because the saline immersion technique will occur EBUS images of hyperechoic points which resemble EBUS image of GGN. EBUS visualization: The operator advances the US probe from the working channel of the 4-mm bronchoscope towards the periphery and stops when some resistance is felt. The duration of X-ray fluoroscopy should be limited as much as possible; also, an iris of the fluoroscopy machine should be used for fluoroscopy. Scanning while pulling back the probe from the distal site to the proximal site reduces strain on the probe and provides clear EBUS images. We have reported that EBUS imaging of PPLs can be used to diagnose and assess the degree of differentiation between benign and malignant lesions3. PPLs are classified as type I if the internal echoes are homogeneous, type III if the internal echoes are heterogeneous, and type II if there are mainly hyperechoic lines and dots near the probe. About 92% of type I lesions were benign, whereas 99% of type II and type III lesions were malignant. The positional relationship between the probe and a PPL is classified as “within” (probe placement within a lesion), when the 360 area around the probe is entirely surrounded by the lesion; and “adjacent to” (probe is in contact with a lesion) when a lesion is depicted, but the 360 area around the probe is not entirely surrounded by the lesion. Higher diagnostic yields have also been reported for lesions with a positive bronchus sign on computed tomography. Minezawa et al.4 reported that the CT bronchus sign was a significant predictive factor for successful bronchoscopic diagnosis in the multivariate analysis. We believe that bronchoscopists should trace the accurate bronchus leading to the PPL on CT axial images. When the lesion located in the middle lobe, the lingular segment, or bilateral lower lobes, we inverse CT axial images right to left, or left to right for watching the bronchus from the cranial site. When the lesion located in the right upper lobe, we rotate CT axial images counterclockwise 90 degrees. When the lesion located in the left superior segment, we rotate CT axial images clockwise 90 degrees. While tracing the bronchus on CT images, we could draw the illustration of the bronchus leading to PPLs. We usually use virtual bronchoscopic navigation (VBN) and compare the hand-written illustration of the bronchus leading to PPLs. Asano et al.5 reported that the diagnostic yield by EBUS-GS and VBN was between 63.3 and 84.4% in reports on VBN for PPLs searched in PubMed as of November 2013. When the ultrasonic probe advanced to the different bronchus a little far from the target lesion, EBUS image is invisible. In this case, we should change the direction of the tip of the bronchoscope using the up and down lever of the
January 2017
bronchoscope under fluoroscopy. We select the direction of the tip of the bronchoscope for facing the target lesion, and pull back and push the probe/GS for trying to insert the target lesion. When the ultrasonic probe advanced to the bronchus adjacent to the target lesion, EBUS image is called as “adjacent to.” In this case, we could change the direction of the tip of the bronchoscope using the up and down lever of the bronchoscope under the EBUS image. We use the up or down lever of the bronchoscope for changing the position of the probe and GS (probe/GS) to be close to the target lesion on EBUS image. Then we keep the same angle of the tip of the bronchoscope, and pull back and push the probe/GS for trying to insert the target lesion. 6) Cytology and tissue biopsy from the guide sheath The GS tip is placed within or adjacent to the PPL before passing the brush and biopsy forceps through the GS. References: 1. Kurimoto N, Fielding D, Musani A. Endobronchial Ultrasonography. 2011, Willy Blackwell. 2. Kurimoto N, Miyazawa T, Okimasa S, Maeda A, Oiwa H, Miyazu Y, Murayama M. Endobronchial ultrasonography using a guide sheath increases the ability to diagnose peripheral pulmonary lesions endoscopically. CHEST 2004; 126: 959-65. 3. Kurimoto N, Murayama M, Yoshioka S, Nishisaka T. Analysis of the internal structure of peripheral pulmonary lesions using endobronchial ultrasonography. CHEST 2002; 122: 1887-94. 4. Minezawa T, Okamura T, Yatsuya H, et al. Bronchus sign on thinsection computed tomography is a powerful predictive factor for successful transbronchial biopsy using endobronchial ultrasound with a guide sheath for small peripheral lung lesions: a retrospective observational study. BMC Med Imaging. 2015 21; 15:21. 5. Asano F, Eberhardt R, Herth F. Virtual Bronchoscopic Navigation for Peripheral Pulmonary Lesions. Respiration 2014; 88: 430-440. Keywords: bronchoscopy, peripheral pulmonary lesion, guide sheath, EBUS
SC19.02 Invasive Staging of Lung Cancer: EBUS, EUS and Beyond Kazuhiro Yasufuku Division of Thoracic Surgery, Toronto General Hospital, Univeristy of Toronto, Toronto/ ON/Canada Despite the advances in surgical treatment and multimodality treatment, lung cancer is still the leading cause of death from malignant disease worldwide. Accurate staging is important not only to determine the prognosis
Abstracts
S121
but also to decide the most suitable treatment plan. During the staging process of non-small cell lung cancer (NSCLC), mediastinal lymph node staging is one of the most important factors that affect the patient outcome. Non-invasive staging such as computed tomography (CT) and positron emission tomography (PET) indicate size and metabolic activity, respectively. However imaging alone is inaccurate and therefore tissue sampling is the preferred and most reliable. Surgical staging by mediastinoscopy has been the gold standard for mediastinal lymph node staging but requires general anesthesia and complications cannot be ignored. Endoscopic ultrasound techniques provide a minimally invasive alternative for surgical staging. The current available endoscopic ultrasound techniques for mediastinal staging include transesophageal endoscopic ultrasound guided fine needle aspiration (EUS-FNA) and endobronchial ultrasound guided transbronchial needle aspiration (EBUSTBNA). Both procedures can be performed in an outpatient setting under local anesthesia. EUS-FNA is a sensitive and safe method of evaluating the inferior mediastinal nodes (stations 7, 8, and 9) and some parts of the anterior mediastinal nodes if the lymph nodes are accessible from the esophagus. However, in spite of the strength of EUS-FNA for evaluating the inferior mediastinal nodes, its ability to evaluate lesions anterior to the trachea is limited. On the other hand, EBUS-TBNA has reach to the paratracheal and subcarinal (stations 2R, 2L, 4R, 4L, 7), as well as the N1 lymph nodes (stations 10, 11, 12). In experienced hands, EBUS can be used through the esophagus for a EUS-like approach to the inferior mediastinal lymph nodes. Thus, EUS-FNA and EBUSTBNA are complementary methods for lymph node staging in lung cancer and most of the mediastinum and the hilum can be evaluated with these endoscopic procedures. Aortic nodes (stations 5 and 6) are exceptions and must be evaluated by surgical methods (anterior mediastinotomy, VATS, thoracotomy). Based on the current evidence, EBUS-TBNA and EUS-FNA presents a minimally invasive endoscopic procedure as an alternative to mediastinoscopy for mediastinal staging of NSCLC with discrete N2 or N3 lymph node enlargement, provided negative results are confirmed by surgical staging. EBUS-TBNA can access all lymph nodes accessible by mediastinoscopy as well as hilar (N1) lymph nodes. EUSFNA has access to the inferior mediastinal lymph nodes not accessible by mediastinoscopy. EBUS-TBNA and/or EUS-FNA have in fact replaced mediastinoscopy in many patients with diffuse mediastinal adenopathy, where a simple tissue diagnosis is required to determine treatment. When combined the techniques offer safe and accurate assessment of mediastinum, with accuracy surpassing that of the pervious gold standard e cervical mediastinoscopy. EBUS-TBNA and/or EUS-FNA can also