A Case of Asymptomatic Intratracheal Schwannom

Abstract

INTRODUCTION: Primary tracheal tumors are rare. They are much less common than bronchial tumors. Most of primary tracheal tumors are either squamous cell carcinoma or adenoid cystic carcinoma. We are presenting a case of schwannoma which is a very rare intratracheal tumor., CASE PRESENTATION: 63 year old male patient came to pulmonary clinic for further evaluation of abnormal imaging.Patient reported shortness of breath on heavy exertion and occasional cough.Patient denied chest pain, weight loss, fever,chills, night sweats or hemoptysis. Patient has past medical history of diabetes, hypertension, dyslipidemia, hypothyroidism, and coronary artery disease.His medications include aspirin, metoprolol, amlodipine, Lipitor and levothyroxine . Patient reported remote history of thyroid cancer status post radiation in 1980s. He also has history of prostate cancer status post surgery and radiation.He has 20 pack year smoking history and quit smoking 15 years ago. Patient reported exposure to agent orange. On examination, patient is afebrile, hemodynamically stable with respiratory rate of 15 and pulse ox saturation of 98%. Chest examination exhibited occasional inspiratory wheeze on central upper chest, otherwise unremarkable. Complete blood count, complete metabolic profile and coagulation studies are normal. Chest roentgenogram showed 1.6 cm sized polyp in the proximal trachea. Inspiratory peak flow was below 100 litre/minute; however, there was no plateau in the inspiratory flow-volume loop. Computed tomography (CT) scan of chest showed 1.2 cm nodular lesion in lower cervical trachea contiguous with the posterior wall. There was no mediastinal or lung parenchymal abnormality seen. Subsequently, bronchoscopy was done which showed intra tracheal lesion with smooth surface obstructing more than 70% lumen of trachea. PET scan was negative for any FDG activity. Patient underwent rigid bronchosocpy with debulking and cauterization of lesion. Immunohistochemical stain was positive for S 100 stain and microscopic exam of the specimen showed spindle cell tumor consistent with Schwannoma., DISCUSSION: Most common symptoms with tracheal tumors are cough, dyspnea, wheezing and hemoptysis. When tracheal tumor is suspected, the most important and preferred test for diagnosis is rigid bronchoscopy. Compared to flexible bronchoscopy, rigid bronchoscopy provides more secure control of the obstructed airway and control of any potential bleeding. The standard treament for these tumors is circumferential resection with tracheal reconstruction. Endoscopic laser resection has been successfully used for benign tracheal tumors. Primary neurogenic tumors of trachea (schwannoma) are extremely uncommon. There have been less than 35 cases reported in the literature. Patients are generally asymptomatic until more than half of the cross sectional area of the trachea is obstructed by the tumor, at which point, obstructive symptoms like dyspnea or cough are seen. In our case, trachea was obstructed by about 70% of its lumen, but patient still did not have any significant symptoms. Strong expression of S-100 is associated with benign tumors, whereas minimal or only focal expression of this protein is suggestive of a malignant lesion., CONCLUSIONS: Primary tracheal schwannoma are very rare tumors. Some of them can be asymptomatic and incidentally found on Chest roentgenogram or CT chest. When tracheal tumor is suspected, rigid bronchoscopy is preferred than flexible bronchosocpy as it provides more secure control of airway or any potential bleeding while resection., Reference #1 Gaissert HA, Grillo HC, Shadmehr MB, et al. Uncommon primary tracheal tumors. Ann Thorac Surg 2006;82:268 -73., Reference #2 Dorfman J, Jamison BM, Morin JE. Primary tracheal schwannoma. Ann Thorac Surg. 2000 Jan;69(1):280-1., Reference #3 Tang LF, Chen ZM, Zou CC. Primary intratracheal neurilemmoma in children: case report and literature review. Pediatr Pulmonol. 2005 Dec;40(6):550-3. Review., DISCLOSURE: The following authors have nothing to disclose: Manish Aggarwal, Yash Trivedi, Askin Uysal, Adam Wellikoff, Cesar Liendo, Shawn Milligan, No Product/Research Disclosure Information, Copyright (C) 2011 by the American College of Chest Physicians