INTRODUCTION: Endobronchial Schwannomas have been previously described. Although this tumor is typically benign, it has been associated with symptomatic airway obstruction and massive hemoptysis. Surgical resection remains the most common treatment for endobronchial Schwannoma (1). We describe the first reported case of an endobronchial Schwannoma treated with Argon Plasma Coagulation (APC) during flexible bronchoscopy.
CASE PRESENTATION: A 38 year-old female with history of asthma presented to the emergency department with progressive dyspnea, left sided pleuritic chest pain, and a non-productive cough. She denied recent hemoptysis, fever, weight loss, or night sweats. She reported occasional alcohol and marijuana use, but denied any use of tobacco or other illicit drugs. Her vital signs were normal and physical examination was unremarkable except for findings of abdominal obesity and a healed low transverse scar. Laboratory data were within normal limits. Room air arterial blood gas revealed mild respiratory alkalosis and chest Roentogram was consistent with hyper-expanded lung fields but no evidence of acute cardiopulmonary disease. A CT angiography of the chest ruled out acute pulmonary embolism but revealed a left lower lobe endobronchial mass. The patient was initially treated with bronchodilators and referred to pulmonary medicine for further evaluation. A Flexible bronchoscopy was performed and revealed a large, white, smooth, well-vascularized tumor causing 80% stenosis of the proximal left lower lobe bronchus. Endobronchial biopsies were obtained and showed spindle cell tumor with histological features of neurogenic tumor. Uniform and intense immunostaining for S-100 protein confirmed the diagnosis of endobronchial Schwannoma. Due to the location of the tumor, surgical resection would have required left pneumonectomy. In order to spare the patient a pneumonectomy, bronchoscopic endobronchial resection was successfully performed using APC. Complete tumor ablation lead to minimal residual stenosis with an estimated procedure time of 70 minutes. The patient reported an immediate improvement in her dyspnea. Follow up bronchoscopy done at 2 months revealed evidence of granulation tissue with fibrin deposition. This was ablated with APC applications. Surveillance bronchoscopy done at 6 months showed that her airways remained patent, and the patient reported continued relief from her dyspnea.
DISCUSSIONS: Endobronchial Schwannomas are rare benign neurogenic tumors. They can appear in any region of the tracheo-bronchial tree and association with neurofibromatosis has been described. Diagnosis is established by histology where degenerative changes and marked nuclear atypia can be seen. Endoscopic treatment has been proposed for small endoluminal Schwannoma with a low probability of recurrence. Nd-YAG laser resection and snare electrocautery are the current described endoscopic treatment of choice (2); however, APC has proven successful in the treatment of endobronchial neoplasms and its safety profile may be more favorable than the Nd-YAG laser. We report the first case of successful ablation of an endobronchial Schwannoma with APC and which effectively maintained patency of the airway at six months. This treatment has allowed our young patient to avoid a pneumonectomy.
CONCLUSION: Argon Plasma Coagulation can be safely used as an effective treatment for endobronchial Schwannomas.
DISCLOSURE: Kevin O’Neal, No Financial Disclosure Information; No Product/Research Disclosure Information