Posterior Mediastinal Schwannoma Invading Into the Spinal Canal: A Rare Case Report and Review of Literature

Abstract

SESSION TITLE: Pulmonary Manifestations of Systemic Disease 1 SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Schwannoma constitutes about 75% of benign neurogenic tumors found in the posterior mediastinum. Only 9.8% of these neurogenic tumors extend into the intervertebral foramina (dumbbell tumors). We are describing a case of a large 11cm right sided posterior mediastinal schwannoma extending into the spinal canal with no significant neurological compromises. CASE PRESENTATION: A 30-year-old ten-day post-partum Caucasian female presented with acute onset of severe right-sided back pain. She had a history of asthma, systemic lupus erythematosus, Antiphospholipid antibody syndrome and pre-eclampsia during her recent pregnancy. She was a life-long non-smoker with no family cancer history. Physical exam revealed no spinal or flank tenderness. She was noted to have mild leukocytosis and anemia. Chest X-ray revealed a large mass in the posterior mediastinum pressing on the neural foramen [Figure 1]. Computerized tomography and magnetic resonance imaging scans of chest confirmed the presence of a well-defined heterogenous 11cm mass extending into the right T3-T4 neural foramen associated with mass effect exerted upon the mid and distal airway. Diffused ground-glass opacities were noted in all pulmonary lobes [figure 2]. Bronchoscopy revealed no mass in the main bronchus. Trans-tracheal biopsy of the right lung mass was performed with histological confirmation of Schwannoma. DISCUSSION: Differential diagnoses for a large posterior mediastinal mass includes lymphoma, neurogenic tumors, or primary malignancy. Flow cytometry was negative for monoclonal expansion of B or T cell lymphocytes. Diffused ground-glass opacities were attributed to pulmonary edema in setting of a recent pregnancy complicated by pre-eclampsia. Flow volume loop did not show any evidence of airway obstruction. Most schwannomas invading into the spinal canal are asymptomatic as per our literature review. Erosions of vertebral pedicles or the enlargement of the intervertebral foramen is the radiographic evidence of tumor extension into the spine. Surgical resection is the treatment of choice for the management of posterior mediastinal schwannoma. Minimal invasive video-assisted thoracoscopic surgery is an alternative treatment option that is reported relatively safe, more reliable and less morbidity compared to open surgery. CONCLUSIONS: Schwannoma involving the posterior mediastinum can present with an impressive radiographic finding. Schwannoma extending into the spinal foramen is a relatively rare phenomenon. Reference #1: Akwari OE, P. W. (1978). Dumbbell neurogenic tumors of the mediastinum. Diagnosis and management. Mayo Clinic Proceedings, 53(6), 353-358. Reference #2: Onakpoya UU, A. B. (2017, Jan-Feb). Large posterior mediastinal schwannoma in a 45-year-old woman. Lung India, 109-111. Reference #3: Negri G, B. A. (2013, March). Unusual Presentation of Mediastinal neurogenic Tumours. Case Report in Surgery, 2013. DISCLOSURE: The following authors have nothing to disclose: Hau Chieng, Biplab Saha, Muhammad Imtiaz No Product/Research Disclosure Information