CASE CONFERENCES The Proceduralist Section Editor: George Eapen, M.D.
Bronchoscopic Resection of an Exophytic Endoluminal Tracheal Mass Russell J. Miller1 and Septimiu D. Murgu2 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Navy Medical Center San Diego, San Diego, California; and 2Section of Pulmonary/Critical Care, Department of Medicine, University of Chicago, Chicago, Illinois
A 43-year-old man developed worsening dyspnea in the setting of previously wellcontrolled asthma. Diagnostic evaluation revealed an obstructing mucoepidermoid carcinoma in the trachea. The lesion was bronchoscopically resected, resulting in complete relief of symptoms. A 43-year-old man was evaluated for progressively limiting exertional dyspnea, wheezing that was most prominent in the supine position, and difficulty clearing secretions from his airway. The patient had been treated for asthma since childhood, but noticed increasing symptoms over the prior 4 months. Dyspnea and wheezing were not responsive to an inhaled corticosteroid or bronchodilators. He was a life-long nonsmoker and had no other symptoms or significant medical history. A computed tomography (CT) scan of the chest showed a large endoluminal tracheal mass just proximal to the main carina without evidence of extraluminal extension (Figure 1). He was referred for bronchoscopic biopsy and airway stabilization. Examination by flexible bronchoscopy revealed a vascular polypoid mass in the lower trachea with near complete luminal obstruction. Because of the degree of airway narrowing and the highly vascularized appearance of the tumor, we believed that tissue sampling and restoration of airway patency would be more safely done by rigid bronchoscopy. After biopsies were obtained, a neodymium:yttrium–aluminum–garnet (Nd:YAG) laser was used to devitalize the tumor. The lesion was then cored out
Figure 1. (A) Axial view in lower trachea showing the tumor base of implantation on the left anterolateral tracheal wall, without extension outside the airway wall (arrow shows normal cartilage surrounding tumor. (B) Coronal view shows vertical extent and tumor location with respect to the main carina.
(Received in original form August 3, 2013; accepted in final form August 14, 2013 ) Correspondence and requests for reprints should be addressed to Russell Miller, M.D., Naval Medical Center San Diego, 34800 Bob Wilson Drive, San Diego, CA 92134. E-mail: [email protected] Ann Am Thorac Soc Vol 10, No 6, pp 697–700, Dec 2013 Copyright © 2013 by the American Thoracic Society DOI: 10.1513/AnnalsATS.201308-252EM Internet address: www.atsjournals.org
Case Conferences: The Proceduralist
697
CASE CONFERENCES mechanically, using the bevel edge of the rigid bronchoscope (Figures 2 and 3). Complete airway patency was achieved without complications (Figure 4). Histopathologic examination showed the tumor to be a lowgrade mucoepidermoid carcinoma (Figure 5).
Discussion Central airway obstruction should be considered in patients who present with new-onset asthma in adulthood or with significant worsening of relatively stable asthma. When a focal obstructing lesion is found, careful consideration of all therapeutic options is imperative. Certain tracheal lesions, like the tumor we found in our patient, are slow growing, and in the absence of other associated pulmonary or cardiac pathology, dyspnea is often a late finding. Indeed, our patient had relatively mild dyspnea despite near complete tracheal obstruction. In an adult, exertional dyspnea from central airway obstruction generally indicates a tracheal diameter of less than 8 mm. Dyspnea at rest suggests a diameter of less than 5 mm. However, given the wide variability in normal tracheal diameters, absolute measurements are less predictive of symptoms than the percentage reduction in the luminal cross-sectional area. If impending respiratory failure is deemed likely, immediate steps should be taken to secure the airway in a controlled fashion. Expeditious thoracic surgery, interventional pulmonology, and anesthesia consultations are advisable. In patients not at immediate risk for respiratory failure, further preoperative assessment is advised to determine tumor size, location, extent, mucosal abnormalities, and the degree of airflow limitation attributable to the tumor. CT imaging after intravenous injection of contrast can help define the lesion in relation to the surrounding mediastinal structures and to evaluate for extraluminal extension. CT scanning can be used to estimate the degree of airway narrowing; however, mucosal secretions or blood can result in an erroneous overestimate of narrowing through volume averaging. Pulmonary function testing is used to assess airflow limitation during inspiration and expiration and to allow for quantification of functional improvement after intervention. The expected abnormality related to intrathoracic central airway obstruction is truncation of both the inspiratory and 698
Figure 2. Exophytic endoluminal obstruction visualized through rigid bronchoscope (arrow shows vascular area).
Figure 3. Neodymium:yttrium–aluminum–garnet (Nd:YAG) laser in vaporization mode to resect tumor base.
Figure 4. Patent airway at completion of procedure (arrow shows charring at the base of implantation).
AnnalsATS Volume 10 Number 6 | December 2013
CASE CONFERENCES
Figure 5. Histophotomicrograph of the mucoepidermoid carcinoma, demonstrating the presence of mucus-producing cells alternating with islands of squamous cells. (Hematoxylin and eosin stain, 3200.)
expiratory limbs on a flow–volume loop. Pulmonary function testing was not performed on our patient, given the high degree of airway narrowing. Bronchoscopy provides real-time quantitative information (by performing morphometric bronchoscopy if necessary) and can distinguish blood, secretions, and necrotic tissue from actual tumor. Bronchoscopy should be performed with adequate precautions in patients with severe tracheal obstruction, because of the potential for worsening airway compromise. In cases of large central airway tumors, even trivial bleeding can result in complete airway obstruction. Thus, in certain cases, biopsy should be deferred until appropriate safety measures including rigid bronchoscopy capability is available. In our case, given the vascular tumor pattern and the clinical need
to restore airway patency for symptomatic relief, we elected to biopsy the lesion at the time of rigid bronchoscopy. Treatment options for purely endoluminal exophytic airway tumors are typically dictated by a combination of the patient’s symptoms, tumor type, extent of airway narrowing, and local expertise. For certain airway tumors (i.e., typical carcinoid) without airway wall involvement detected by CT imaging and highfrequency endobronchial ultrasound (20MHz balloon-based radial probe), bronchoscopic therapy may be curative. In our patient we used an Nd:YAG laser to coagulate the tumor before resection. The deep coagulation effects offered by the 1,064-nm wavelength when used at low power density (i.e., z1 cm proximal to the tumor) make this laser preferable in our
practice over other commonly used lasers (Table 1). For lesions deemed unresectable, pure endoluminal exophytic tumors can be managed by endoluminal debulking/ resection. Stenting is reserved for tumors with an associated component of extrinsic compression or in cases of airway wall instability (i.e., malacia due to cartilaginous wall destruction). Bronchoscopic resection is associated with less morbidity than surgery, but because resection margins may not be well defined, it is not usually considered a curative intervention. Surgical options should still be explored after airway patency is restored. In our patient, rigid bronchoscopy was performed primarily for biopsy and symptomatic relief. Mucoepidermoid carcinoma is a rare tumor comprising 0.1–0.2% of thoracic malignancies. The peak occurrence is in the third decade of life and there is no association with alcohol or tobacco use. Morphologically, these tumors are well circumscribed and polypoid in nature, and histological classification is based on the degree of differentiation. Low-grade tumors are typically slow growing, and patients have 100% 5-year survival when the tumor is completely resected. There is a theoretical risk of transformation to high-grade tumor over time. High-grade tumors are often rapidly progressive, and patients have an average life expectancy of 2 years. In low-grade tumors, complete bronchoscopic resection is sometimes definitive. In the absence of visible residual tumor, the need for surgical intervention after endoscopic resection is controversial. High-frequency endobronchial ultrasound can assist in
Table 1. Characteristics of commonly used lasers in bronchoscopy Type of Laser Used in Airway
Wavelength (nm)
Coagulation
Cutting Precision
Vaporization
Absorption
Nd:YAG
1,064
11
1
111
Nd:YAP Ho:YAG KTP CO2 Thulium Diode† Argon
1,340 2,100 532 10,600 2,000 1,318 516
111 1 1 1 111 11 111
11 111 11 111 111 11 1
1 11 11 111 1 1 1
Proteins of any opaque tissue Water Water Hemoglobin Water Water Water Hemoglobin
Depth of Penetration* (mm) 5–15 3 0.5 1 0.1 ,1 3–5 1
Definition of abbreviations: Ho:YAG = holmium:yttrium–aluminum–garnet; KTP = potassium–titanyl–phosphate; Nd:YAG = neodymium:yttrium–aluminum– garnet; Nd:YAP = neodymium:yttrium–aluminum–perovskite. Definition of symbols: 1 = poor; 11 = good; 111 = excellent. *Penetration depth also depends on tissue color, water content, and power density applied. † Diode lasers are available in multiple wavelengths that alter physical properties.
Case Conferences: The Proceduralist
699
CASE CONFERENCES evaluating the depth of invasion and can aid in assessing the potential benefit in patients considering definitive surgical resection.
Follow-Up Our patient experienced complete relief of symptoms after the procedure. Repeat
flexible bronchoscopy performed 1 month later was notable for a small residual tumor at the resected site. This was bronchoscopically treated with argon plasma coagulation. Surgical consultation was offered to the patient. Carinal resection was deemed likely to be necessary, based on the anatomical location of
Recommended Reading Cavaliere S, Venuta F, Foccoli P, Toninelli C, La Face B. Endoscopic treatment of malignant airway obstructions in 2,008 patients. Chest 1996;110:1536–1542. [Published erratum appears in Chest 111: 1476.] Ha SY, Han J, Lee JJ, Kim YE, Choi Y-L, Kim HK. Mucoepidermoid carcinoma of tracheobronchial tree: clinicopathological study of 31 cases. Korean J Pathol 2011;45:175–181.
700
the tumor. Given the expected morbidity of the surgery, the patient opted for close serial observation with bronchoscopic treatment in the event of recurrence. n Author disclosures are available with the text of this article at www.atsjournals.org.
Kajiwara N, Kakihana M, Usuda J, Ohira T, Kawate N, Ikeda N. Interventional management for benign airway tumors in relation to location, size, character and morphology. J Thorac Dis 2011;3:221–230. Macchiarini P. Primary tracheal tumours. Lancet Oncol 2006;7:83–91. Murgu S, Colt HG. Morphometric bronchoscopy in adults with central airway obstruction: case illustrations and review of the literature. Laryngoscope 2009;119:1318–1324. Peng Q, Juzeniene A, Chen J, Svaasand LO, Warloe T, Giercksky K-E, Moan J. Lasers in medicine [abstract]. Rep Prog Phys 2008;71:1–28.
AnnalsATS Volume 10 Number 6 | December 2013
Bronchoscopic Resection of an Exophytic Endoluminal Tracheal Mass Russell J. Miller1 and Septimiu D. Murgu2 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Navy Medical Center San Diego, San Diego, California; and 2Section of Pulmonary/Critical Care, Department of Medicine, University of Chicago, Chicago, Illinois
A 43-year-old man developed worsening dyspnea in the setting of previously wellcontrolled asthma. Diagnostic evaluation revealed an obstructing mucoepidermoid carcinoma in the trachea. The lesion was bronchoscopically resected, resulting in complete relief of symptoms. A 43-year-old man was evaluated for progressively limiting exertional dyspnea, wheezing that was most prominent in the supine position, and difficulty clearing secretions from his airway. The patient had been treated for asthma since childhood, but noticed increasing symptoms over the prior 4 months. Dyspnea and wheezing were not responsive to an inhaled corticosteroid or bronchodilators. He was a life-long nonsmoker and had no other symptoms or significant medical history. A computed tomography (CT) scan of the chest showed a large endoluminal tracheal mass just proximal to the main carina without evidence of extraluminal extension (Figure 1). He was referred for bronchoscopic biopsy and airway stabilization. Examination by flexible bronchoscopy revealed a vascular polypoid mass in the lower trachea with near complete luminal obstruction. Because of the degree of airway narrowing and the highly vascularized appearance of the tumor, we believed that tissue sampling and restoration of airway patency would be more safely done by rigid bronchoscopy. After biopsies were obtained, a neodymium:yttrium–aluminum–garnet (Nd:YAG) laser was used to devitalize the tumor. The lesion was then cored out
Figure 1. (A) Axial view in lower trachea showing the tumor base of implantation on the left anterolateral tracheal wall, without extension outside the airway wall (arrow shows normal cartilage surrounding tumor. (B) Coronal view shows vertical extent and tumor location with respect to the main carina.
(Received in original form August 3, 2013; accepted in final form August 14, 2013 ) Correspondence and requests for reprints should be addressed to Russell Miller, M.D., Naval Medical Center San Diego, 34800 Bob Wilson Drive, San Diego, CA 92134. E-mail: [email protected] Ann Am Thorac Soc Vol 10, No 6, pp 697–700, Dec 2013 Copyright © 2013 by the American Thoracic Society DOI: 10.1513/AnnalsATS.201308-252EM Internet address: www.atsjournals.org
Case Conferences: The Proceduralist
697
CASE CONFERENCES mechanically, using the bevel edge of the rigid bronchoscope (Figures 2 and 3). Complete airway patency was achieved without complications (Figure 4). Histopathologic examination showed the tumor to be a lowgrade mucoepidermoid carcinoma (Figure 5).
Discussion Central airway obstruction should be considered in patients who present with new-onset asthma in adulthood or with significant worsening of relatively stable asthma. When a focal obstructing lesion is found, careful consideration of all therapeutic options is imperative. Certain tracheal lesions, like the tumor we found in our patient, are slow growing, and in the absence of other associated pulmonary or cardiac pathology, dyspnea is often a late finding. Indeed, our patient had relatively mild dyspnea despite near complete tracheal obstruction. In an adult, exertional dyspnea from central airway obstruction generally indicates a tracheal diameter of less than 8 mm. Dyspnea at rest suggests a diameter of less than 5 mm. However, given the wide variability in normal tracheal diameters, absolute measurements are less predictive of symptoms than the percentage reduction in the luminal cross-sectional area. If impending respiratory failure is deemed likely, immediate steps should be taken to secure the airway in a controlled fashion. Expeditious thoracic surgery, interventional pulmonology, and anesthesia consultations are advisable. In patients not at immediate risk for respiratory failure, further preoperative assessment is advised to determine tumor size, location, extent, mucosal abnormalities, and the degree of airflow limitation attributable to the tumor. CT imaging after intravenous injection of contrast can help define the lesion in relation to the surrounding mediastinal structures and to evaluate for extraluminal extension. CT scanning can be used to estimate the degree of airway narrowing; however, mucosal secretions or blood can result in an erroneous overestimate of narrowing through volume averaging. Pulmonary function testing is used to assess airflow limitation during inspiration and expiration and to allow for quantification of functional improvement after intervention. The expected abnormality related to intrathoracic central airway obstruction is truncation of both the inspiratory and 698
Figure 2. Exophytic endoluminal obstruction visualized through rigid bronchoscope (arrow shows vascular area).
Figure 3. Neodymium:yttrium–aluminum–garnet (Nd:YAG) laser in vaporization mode to resect tumor base.
Figure 4. Patent airway at completion of procedure (arrow shows charring at the base of implantation).
AnnalsATS Volume 10 Number 6 | December 2013
CASE CONFERENCES
Figure 5. Histophotomicrograph of the mucoepidermoid carcinoma, demonstrating the presence of mucus-producing cells alternating with islands of squamous cells. (Hematoxylin and eosin stain, 3200.)
expiratory limbs on a flow–volume loop. Pulmonary function testing was not performed on our patient, given the high degree of airway narrowing. Bronchoscopy provides real-time quantitative information (by performing morphometric bronchoscopy if necessary) and can distinguish blood, secretions, and necrotic tissue from actual tumor. Bronchoscopy should be performed with adequate precautions in patients with severe tracheal obstruction, because of the potential for worsening airway compromise. In cases of large central airway tumors, even trivial bleeding can result in complete airway obstruction. Thus, in certain cases, biopsy should be deferred until appropriate safety measures including rigid bronchoscopy capability is available. In our case, given the vascular tumor pattern and the clinical need
to restore airway patency for symptomatic relief, we elected to biopsy the lesion at the time of rigid bronchoscopy. Treatment options for purely endoluminal exophytic airway tumors are typically dictated by a combination of the patient’s symptoms, tumor type, extent of airway narrowing, and local expertise. For certain airway tumors (i.e., typical carcinoid) without airway wall involvement detected by CT imaging and highfrequency endobronchial ultrasound (20MHz balloon-based radial probe), bronchoscopic therapy may be curative. In our patient we used an Nd:YAG laser to coagulate the tumor before resection. The deep coagulation effects offered by the 1,064-nm wavelength when used at low power density (i.e., z1 cm proximal to the tumor) make this laser preferable in our
practice over other commonly used lasers (Table 1). For lesions deemed unresectable, pure endoluminal exophytic tumors can be managed by endoluminal debulking/ resection. Stenting is reserved for tumors with an associated component of extrinsic compression or in cases of airway wall instability (i.e., malacia due to cartilaginous wall destruction). Bronchoscopic resection is associated with less morbidity than surgery, but because resection margins may not be well defined, it is not usually considered a curative intervention. Surgical options should still be explored after airway patency is restored. In our patient, rigid bronchoscopy was performed primarily for biopsy and symptomatic relief. Mucoepidermoid carcinoma is a rare tumor comprising 0.1–0.2% of thoracic malignancies. The peak occurrence is in the third decade of life and there is no association with alcohol or tobacco use. Morphologically, these tumors are well circumscribed and polypoid in nature, and histological classification is based on the degree of differentiation. Low-grade tumors are typically slow growing, and patients have 100% 5-year survival when the tumor is completely resected. There is a theoretical risk of transformation to high-grade tumor over time. High-grade tumors are often rapidly progressive, and patients have an average life expectancy of 2 years. In low-grade tumors, complete bronchoscopic resection is sometimes definitive. In the absence of visible residual tumor, the need for surgical intervention after endoscopic resection is controversial. High-frequency endobronchial ultrasound can assist in
Table 1. Characteristics of commonly used lasers in bronchoscopy Type of Laser Used in Airway
Wavelength (nm)
Coagulation
Cutting Precision
Vaporization
Absorption
Nd:YAG
1,064
11
1
111
Nd:YAP Ho:YAG KTP CO2 Thulium Diode† Argon
1,340 2,100 532 10,600 2,000 1,318 516
111 1 1 1 111 11 111
11 111 11 111 111 11 1
1 11 11 111 1 1 1
Proteins of any opaque tissue Water Water Hemoglobin Water Water Water Hemoglobin
Depth of Penetration* (mm) 5–15 3 0.5 1 0.1 ,1 3–5 1
Definition of abbreviations: Ho:YAG = holmium:yttrium–aluminum–garnet; KTP = potassium–titanyl–phosphate; Nd:YAG = neodymium:yttrium–aluminum– garnet; Nd:YAP = neodymium:yttrium–aluminum–perovskite. Definition of symbols: 1 = poor; 11 = good; 111 = excellent. *Penetration depth also depends on tissue color, water content, and power density applied. † Diode lasers are available in multiple wavelengths that alter physical properties.
Case Conferences: The Proceduralist
699
CASE CONFERENCES evaluating the depth of invasion and can aid in assessing the potential benefit in patients considering definitive surgical resection.
Follow-Up Our patient experienced complete relief of symptoms after the procedure. Repeat
flexible bronchoscopy performed 1 month later was notable for a small residual tumor at the resected site. This was bronchoscopically treated with argon plasma coagulation. Surgical consultation was offered to the patient. Carinal resection was deemed likely to be necessary, based on the anatomical location of
Recommended Reading Cavaliere S, Venuta F, Foccoli P, Toninelli C, La Face B. Endoscopic treatment of malignant airway obstructions in 2,008 patients. Chest 1996;110:1536–1542. [Published erratum appears in Chest 111: 1476.] Ha SY, Han J, Lee JJ, Kim YE, Choi Y-L, Kim HK. Mucoepidermoid carcinoma of tracheobronchial tree: clinicopathological study of 31 cases. Korean J Pathol 2011;45:175–181.
700
the tumor. Given the expected morbidity of the surgery, the patient opted for close serial observation with bronchoscopic treatment in the event of recurrence. n Author disclosures are available with the text of this article at www.atsjournals.org.
Kajiwara N, Kakihana M, Usuda J, Ohira T, Kawate N, Ikeda N. Interventional management for benign airway tumors in relation to location, size, character and morphology. J Thorac Dis 2011;3:221–230. Macchiarini P. Primary tracheal tumours. Lancet Oncol 2006;7:83–91. Murgu S, Colt HG. Morphometric bronchoscopy in adults with central airway obstruction: case illustrations and review of the literature. Laryngoscope 2009;119:1318–1324. Peng Q, Juzeniene A, Chen J, Svaasand LO, Warloe T, Giercksky K-E, Moan J. Lasers in medicine [abstract]. Rep Prog Phys 2008;71:1–28.
AnnalsATS Volume 10 Number 6 | December 2013
