Case Study
Schwannoma arising in a bronchogenic cyst wall
Asian Cardiovascular & Thoracic Annals 2015, Vol. 23(3) 328–331 ß The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492314529292 aan.sagepub.com
Koray Aydogdu1, Gokturk Fındık1, Sadi Kaya1, Deniz Koksal2 and Funda Demirag3
Abstract Bronchogenic cysts are congenital malformations thought to originate from the primitive ventral foregut, and they are the most common type of mediastinal cystic lesion. The clinical presentation of a bronchogenic cyst is variable, from respiratory distress at birth to late appearance of symptoms. Most bronchogenic cysts originate in the mediastinum, and 15% to 20% occur in the lung parenchyma. Various malignant transformations have been reported in the literature. In this report, we describe a case of schwannoma in an intrapulmonary bronchogenic cyst wall in a 38-year-old man, which was found incidentally during a routine examination.
Keywords Bronchogenic cyst, mediastinal cyst, neurilemmoma
Introduction Bronchogenic cysts are congenital cystic lesions thought to result from abnormal budding of the ventral foregut. They are generally found in the mediastinum, and 15% to 20% occur in the lung parenchyma. They are usually asymptomatic but tracheal deviation, difficulty in swallowing, hoarseness, pain, a mass on the neck, or shortness of breath can occur because of compression by these cysts on neighboring structures in the mediastinum. Furthermore, there is some risk of malignant transformation of a bronchogenic cyst. In the literature, there are few case reports of various types of malignant transformation, but to the best of our knowledge, a schwannoma developing from the bronchogenic cyst wall has not been reported previously.
Case report A 38-year-old man with no previous related complaint was admitted to our clinic when a left hilar mass was seen in a chest radiograph during a routine examination. A computed tomography scan showed a 3 3cm mass with soft tissue density in the left hilar region (Figure 1). On initial physical examination, breath sounds were normal in both lungs. All routine laboratory tests, such as biochemistry, coagulation
parameters, and thyroid function tests, were normal. Fiberoptic bronchoscopy showed no endobronchial lesion. Due to the mediastinal localization of the mass, a transthoracic fine-needle aspiration biopsy could not be performed for diagnostic purposes. For a remote scan and diagnosis, 18 F-fluorodeoxyglucose positron-emission tomography was used, and heterogeneous uptake (maximum standardized uptake value 2.5) was detected in a mass lesion with a soft tissue density adjacent to the left hilar lingular segment. Malignancy could not be ruled out by these findings. We performed a left thoracotomy for both diagnosis and treatment. During the operation, a lesion of approximately 3 cm with a soft consistency was 1 Department of Thoracic Surgery, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey 2 Department of Chest Diseases, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey 3 Department of Pathology, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey
Corresponding author: Koray Aydogdu, Department of Thoracic Surgery, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey. Email: [email protected]
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Figure 1. (A) Radiograph showing the left hilar sited lesion. (B) Computed tomography showing a 3 3-cm mass with soft tissue density in the left hilar site.
Figure 2. The excision steps of the lesion.
palpated in the upper lobe near to the left hilar region. On puncture of the lesion, clear serous liquid was obtained, and it was determined to be a cystic lesion. The cyst was dissected from the surrounding tissues with its integrity preserved, and the bronchial connection was found and broken. Finally, the cyst was removed totally (Figure 2). Histopathological examination revealed that the wall of the cyst was lined by upper respiratory tract epithelium, and tumor structures formed by spindle cells were observed. In an immunohistochemical study, the tumor cells were seen to be diffusely and strongly positive for S100 protein. Bronchial epithelial cells were positive for keratin-7. No necrosis or areas of mitotic activity were observed (Figure 3). It was considered to be a schwannoma that had developed from the bronchogenic cyst wall. There were no complications in the postoperative period. Our patient was examined in the 6th postoperative month, and he is still under our follow-up.
Discussion Bronchogenic cyst is a congenital malformation of the embryonic tracheobronchial tree, and is the most common mediastinal cyst. It is observed not only in infants and children but also in adults.1,2 Bronchogenic cysts are generally found in the mediastinum and within the pulmonary parenchyma. If separation from the respiratory airway occurs early, this results in localization proximal to the tracheobronchial tree in the middle and posterior mediastinum, especially the carina and paratracheal area.1 Later development during branching of the tracheobronchial tree however
favors intrapulmonary growth, and a communicating fistula is commonly present. The fistula is etiologically related to cyst infection and chronic inflammation in this subgroup in which the cyst can rupture into the trachea or pericardial cavity.1 The extrathoracic locations range from the neck to the spinal dura mater to below the diaphragm, including presternal tissues, diaphragm, spine, skin and subcutaneous tissue, pericardium, neck, and abdomen.3,4 They are generally unilocular lesions, and their contents are clear fluid, hemorrhagic secretions, and air. They are lined by ciliated columnar epithelium, and their walls often contain cartilage and bronchial mucous glands.2 Although some bronchogenic cysts are asymptomatic and discovered incidentally on radiography, most cysts are symptomatic and complications are more common in symptomatic patients. The most frequent symptoms are cough, fever, pain, dyspnea, respiratory infection, and wheezing.1,5 Complications resulting from compression of adjacent structures include superior vena caval syndrome, tracheal compression, and dysphagia.5 Pneumothorax is not an uncommon complication, and is usually accompanied by pleuritis. Severe hemoptysis is rarely reported.2 Bronchogenic cysts appear as spherical or oval masses with smooth outlines and are usually unilocular and noncalcified in chest radiographs and computed tomography scans.2 The differential diagnoses of mediastinal cysts include esophageal duplication cyst, neuroenteric cyst, and congenital cystic adenomatoid malformation. Lung abscess, hydatidosis, fungal disease, tuberculosis, infected bullae, vascular malformations, and neoplasms are included in the differential diagnoses of
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Figure 3. (A) Spindle cells around the cystic bronchiole. Hematoxylin and eosin stain, original magnification 200. (B) Keratin-7 positivity in bronchiole epithelium. Keratin-7 stain, original magnification 200. (C, D) The neoplastic cells stained positive for S100 protein.
intraparenchymal cysts. The definitive way to establish the diagnosis is by surgical resection and histopathological examination. Thus surgery may be needed for all radiologically suspected bronchogenic cysts.1,2,6 There is a general consensus on surgical resection of symptomatic cysts when there is intrapulmonary growth and diagnostic uncertainty, but the management of uncomplicated cysts is still controversal.1 Some reports concluded that asymptomatic bronchogenic cysts may become symptomatic with time. Bronchogenic cysts may be associated with potentially serious complications. Because a confident preoperative diagnosis is not always possible, and resection of symptomatic cysts may be associated with greater operative difficulty and more operative or postoperative complications, excision of all suspected bronchogenic cysts is favored in operable candidates.3 On the other hand, the most important issue that should be emphasized is the potential malignant transformation of bronchogenic cysts, although there are just a few case reports of various types of malignant transformation.7,8 Tsai and colleagues1 reviewed 22 cases of bronchogenic cyst with secondary malignancy. The clinical information, malignant subtypes, and outcome of malignant bronchogenic cysts are summarized in their review. Adenocarcinoma was found to be the most common histological subtype; others included carcinoid tumors, squamous cell carcinoma, melanoma, leiomyosarcoma, anaplastic carcinoma, large cell carcinoma, mucoepidermoid carcinoma, and fibrosarcoma.
Although few cases of malignant transformation have been reported, complete surgical resection and thorough pathologic examination should be carried out even if the patients are asymptomatic. Presented at the Annual Meeting of the Turkish Respiratory Society, Turkey, 2012. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest statement None declared.
References 1. Tsai JH, Lee JM, Lin MC and Liau JY. Carcinoid tumor arising in a thymic bronchogenic cyst associated with thymic follicular hyperplasia. Pathol Int 2012; 62: 49–54. 2. Sarper A, Ayten A, Golbasi I, Demircan A and Isin E. Bronchogenic cyst. Tex Heart Inst J 2003; 30: 105–108. 3. Patel SR, Meeker DP, Biscotti CV, Kirby TJ and Rice TW. Presentation and management of bronchogenic cysts in the adult. Chest 1994; 106: 79–85. 4. Petrina A, Boselli C, Cirocchi R, et al. Bronchogenic cyst of the ileal mesentery: a case report and a review of literature J Med Case Rep 2010;4:313. 5. Marshall G, Cheah C and Lenzo N. Bronchogenic cyst with multiple complications. Biomed Imaging Interv J 2007; 3: e42.
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6. Panchanatheeswaran K, Dutta R, Singh KI and Kumar A. Eleven-year experience in thoracoscopic excision of bronchogenic cyst. Asian Cardiovasc Thorac Ann 2012; 20: 570–574. 7. Brassesco MS, Valera ET, Lira RC, et al. Mucoepidermoid carcinoma of the lung arising at the
primary site of a bronchogenic cyst: clinical, cytogenetic, and molecular findings. Pediatr Blood Cancer 2011; 56: 311–313. 8. de Perrot M, Pache JC and Spiliopoulos A. Carcinoma arising in congenital lung cysts. Thorac Cardiovasc Surg 2001; 49: 184–185.
Downloaded from aan.sagepub.com at University of Bath - The Library on June 24, 2015
Schwannoma arising in a bronchogenic cyst wall
Asian Cardiovascular & Thoracic Annals 2015, Vol. 23(3) 328–331 ß The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0218492314529292 aan.sagepub.com
Koray Aydogdu1, Gokturk Fındık1, Sadi Kaya1, Deniz Koksal2 and Funda Demirag3
Abstract Bronchogenic cysts are congenital malformations thought to originate from the primitive ventral foregut, and they are the most common type of mediastinal cystic lesion. The clinical presentation of a bronchogenic cyst is variable, from respiratory distress at birth to late appearance of symptoms. Most bronchogenic cysts originate in the mediastinum, and 15% to 20% occur in the lung parenchyma. Various malignant transformations have been reported in the literature. In this report, we describe a case of schwannoma in an intrapulmonary bronchogenic cyst wall in a 38-year-old man, which was found incidentally during a routine examination.
Keywords Bronchogenic cyst, mediastinal cyst, neurilemmoma
Introduction Bronchogenic cysts are congenital cystic lesions thought to result from abnormal budding of the ventral foregut. They are generally found in the mediastinum, and 15% to 20% occur in the lung parenchyma. They are usually asymptomatic but tracheal deviation, difficulty in swallowing, hoarseness, pain, a mass on the neck, or shortness of breath can occur because of compression by these cysts on neighboring structures in the mediastinum. Furthermore, there is some risk of malignant transformation of a bronchogenic cyst. In the literature, there are few case reports of various types of malignant transformation, but to the best of our knowledge, a schwannoma developing from the bronchogenic cyst wall has not been reported previously.
Case report A 38-year-old man with no previous related complaint was admitted to our clinic when a left hilar mass was seen in a chest radiograph during a routine examination. A computed tomography scan showed a 3 3cm mass with soft tissue density in the left hilar region (Figure 1). On initial physical examination, breath sounds were normal in both lungs. All routine laboratory tests, such as biochemistry, coagulation
parameters, and thyroid function tests, were normal. Fiberoptic bronchoscopy showed no endobronchial lesion. Due to the mediastinal localization of the mass, a transthoracic fine-needle aspiration biopsy could not be performed for diagnostic purposes. For a remote scan and diagnosis, 18 F-fluorodeoxyglucose positron-emission tomography was used, and heterogeneous uptake (maximum standardized uptake value 2.5) was detected in a mass lesion with a soft tissue density adjacent to the left hilar lingular segment. Malignancy could not be ruled out by these findings. We performed a left thoracotomy for both diagnosis and treatment. During the operation, a lesion of approximately 3 cm with a soft consistency was 1 Department of Thoracic Surgery, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey 2 Department of Chest Diseases, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey 3 Department of Pathology, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey
Corresponding author: Koray Aydogdu, Department of Thoracic Surgery, Atatu¨rk Chest Diseases and Thoracic Surgery Research and Training Hospital, Ankara, Turkey. Email: [email protected]
Downloaded from aan.sagepub.com at University of Bath - The Library on June 24, 2015
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Figure 1. (A) Radiograph showing the left hilar sited lesion. (B) Computed tomography showing a 3 3-cm mass with soft tissue density in the left hilar site.
Figure 2. The excision steps of the lesion.
palpated in the upper lobe near to the left hilar region. On puncture of the lesion, clear serous liquid was obtained, and it was determined to be a cystic lesion. The cyst was dissected from the surrounding tissues with its integrity preserved, and the bronchial connection was found and broken. Finally, the cyst was removed totally (Figure 2). Histopathological examination revealed that the wall of the cyst was lined by upper respiratory tract epithelium, and tumor structures formed by spindle cells were observed. In an immunohistochemical study, the tumor cells were seen to be diffusely and strongly positive for S100 protein. Bronchial epithelial cells were positive for keratin-7. No necrosis or areas of mitotic activity were observed (Figure 3). It was considered to be a schwannoma that had developed from the bronchogenic cyst wall. There were no complications in the postoperative period. Our patient was examined in the 6th postoperative month, and he is still under our follow-up.
Discussion Bronchogenic cyst is a congenital malformation of the embryonic tracheobronchial tree, and is the most common mediastinal cyst. It is observed not only in infants and children but also in adults.1,2 Bronchogenic cysts are generally found in the mediastinum and within the pulmonary parenchyma. If separation from the respiratory airway occurs early, this results in localization proximal to the tracheobronchial tree in the middle and posterior mediastinum, especially the carina and paratracheal area.1 Later development during branching of the tracheobronchial tree however
favors intrapulmonary growth, and a communicating fistula is commonly present. The fistula is etiologically related to cyst infection and chronic inflammation in this subgroup in which the cyst can rupture into the trachea or pericardial cavity.1 The extrathoracic locations range from the neck to the spinal dura mater to below the diaphragm, including presternal tissues, diaphragm, spine, skin and subcutaneous tissue, pericardium, neck, and abdomen.3,4 They are generally unilocular lesions, and their contents are clear fluid, hemorrhagic secretions, and air. They are lined by ciliated columnar epithelium, and their walls often contain cartilage and bronchial mucous glands.2 Although some bronchogenic cysts are asymptomatic and discovered incidentally on radiography, most cysts are symptomatic and complications are more common in symptomatic patients. The most frequent symptoms are cough, fever, pain, dyspnea, respiratory infection, and wheezing.1,5 Complications resulting from compression of adjacent structures include superior vena caval syndrome, tracheal compression, and dysphagia.5 Pneumothorax is not an uncommon complication, and is usually accompanied by pleuritis. Severe hemoptysis is rarely reported.2 Bronchogenic cysts appear as spherical or oval masses with smooth outlines and are usually unilocular and noncalcified in chest radiographs and computed tomography scans.2 The differential diagnoses of mediastinal cysts include esophageal duplication cyst, neuroenteric cyst, and congenital cystic adenomatoid malformation. Lung abscess, hydatidosis, fungal disease, tuberculosis, infected bullae, vascular malformations, and neoplasms are included in the differential diagnoses of
Downloaded from aan.sagepub.com at University of Bath - The Library on June 24, 2015
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Figure 3. (A) Spindle cells around the cystic bronchiole. Hematoxylin and eosin stain, original magnification 200. (B) Keratin-7 positivity in bronchiole epithelium. Keratin-7 stain, original magnification 200. (C, D) The neoplastic cells stained positive for S100 protein.
intraparenchymal cysts. The definitive way to establish the diagnosis is by surgical resection and histopathological examination. Thus surgery may be needed for all radiologically suspected bronchogenic cysts.1,2,6 There is a general consensus on surgical resection of symptomatic cysts when there is intrapulmonary growth and diagnostic uncertainty, but the management of uncomplicated cysts is still controversal.1 Some reports concluded that asymptomatic bronchogenic cysts may become symptomatic with time. Bronchogenic cysts may be associated with potentially serious complications. Because a confident preoperative diagnosis is not always possible, and resection of symptomatic cysts may be associated with greater operative difficulty and more operative or postoperative complications, excision of all suspected bronchogenic cysts is favored in operable candidates.3 On the other hand, the most important issue that should be emphasized is the potential malignant transformation of bronchogenic cysts, although there are just a few case reports of various types of malignant transformation.7,8 Tsai and colleagues1 reviewed 22 cases of bronchogenic cyst with secondary malignancy. The clinical information, malignant subtypes, and outcome of malignant bronchogenic cysts are summarized in their review. Adenocarcinoma was found to be the most common histological subtype; others included carcinoid tumors, squamous cell carcinoma, melanoma, leiomyosarcoma, anaplastic carcinoma, large cell carcinoma, mucoepidermoid carcinoma, and fibrosarcoma.
Although few cases of malignant transformation have been reported, complete surgical resection and thorough pathologic examination should be carried out even if the patients are asymptomatic. Presented at the Annual Meeting of the Turkish Respiratory Society, Turkey, 2012. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest statement None declared.
References 1. Tsai JH, Lee JM, Lin MC and Liau JY. Carcinoid tumor arising in a thymic bronchogenic cyst associated with thymic follicular hyperplasia. Pathol Int 2012; 62: 49–54. 2. Sarper A, Ayten A, Golbasi I, Demircan A and Isin E. Bronchogenic cyst. Tex Heart Inst J 2003; 30: 105–108. 3. Patel SR, Meeker DP, Biscotti CV, Kirby TJ and Rice TW. Presentation and management of bronchogenic cysts in the adult. Chest 1994; 106: 79–85. 4. Petrina A, Boselli C, Cirocchi R, et al. Bronchogenic cyst of the ileal mesentery: a case report and a review of literature J Med Case Rep 2010;4:313. 5. Marshall G, Cheah C and Lenzo N. Bronchogenic cyst with multiple complications. Biomed Imaging Interv J 2007; 3: e42.
Downloaded from aan.sagepub.com at University of Bath - The Library on June 24, 2015
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6. Panchanatheeswaran K, Dutta R, Singh KI and Kumar A. Eleven-year experience in thoracoscopic excision of bronchogenic cyst. Asian Cardiovasc Thorac Ann 2012; 20: 570–574. 7. Brassesco MS, Valera ET, Lira RC, et al. Mucoepidermoid carcinoma of the lung arising at the
primary site of a bronchogenic cyst: clinical, cytogenetic, and molecular findings. Pediatr Blood Cancer 2011; 56: 311–313. 8. de Perrot M, Pache JC and Spiliopoulos A. Carcinoma arising in congenital lung cysts. Thorac Cardiovasc Surg 2001; 49: 184–185.
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