THAT NAGGING COUGH: INTRATHORACIC SCHWANNOMA WITH HORNERS SYNDROME

Abstract

SESSION TITLE: Medical Student/Resident Lung Pathology SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Malignant tumors in the mediastinum are unusual, accounting for less than 1% of mediastinal tumors. Of those, neural origin are usually benign in the mediastinum [1]. The most common tumors are located in the posterior mediastinum and are neurogenic such as schwannomas but also may be pleural fibromas. Definitive diagnosis requires tissue sampling [2]. Incidence is extremely rare, with 6% of giant schwannomas originating from the vagus nerve. Currently there are not enough cases to have a prevalence. Horner Syndrome is associated with mediastinal tumors, which is characterized by obstruction of the sympathetic pathway to the eye and face consisting of ipsilateral myosis, partial proptosis and anhidrosis [3]. CASE PRESENTATION: Thirty one-year-old female with a past medical history of two miscarriages was seen in the office for an upper respiratory infection and prescribed antibiotics and ordered a two view chest x-ray which showed a 6 cm round mass in the right upper lobe suspicious for pancoast tumor [Figure 1A, B]. She had been complaining of headaches, right eyelid dropping, dizziness and uneven pupils as her right side was smaller than left. Subsequently had computed tomography (CT) chest showing small right apical mass with fibrous tumor of the pleura with involvement possibly of the nerve sheath measuring 6 cm x 4.8 cm x 5.7 cm [Figure 2A, B]. Patient had CT guided lung biopsy which demonstrated S100, BCL-2 and CD 99+ compatible with schwannoma [Figure 3A-D]. She had positron emission tomography (PET) scan performed which showed intense fluorodeoxyglucose (FDG) uptake in the right apical region with standardized uptake values (SUV) max of 6.7 with no FDG avid thoracic lymphadenopathy, extensive FDG uptake within hypermetabolic fat in the left neck, supraclavicular fossa, and superior right suprarenal fat. Focal FDG uptake localizing to the posterior left neck with SUV max of 3.8. Patient was referred to surgery where she had brachial plexus exploration and dissection of thoracic inlet tumor resected through VATS. DISCUSSION: Neurogenic tumors are the most common type of neoplasia the posterior mediastinum. This consists of schwannomas and neurofibromas along with ganglion neuroblastomas. Recognition of adjacent nerves as well are well-defined margins in the presence of split fat sign may suggest benign tumor [4]. This patient developed a rare association of intrathoracic schwannoma that presented itself as Horner syndrome. Although Horner syndrome is a well-known association of sympathetic chain schwannomas of the neck and malignant lung tumors, it is uncommon for it to be presented as a benign intrathoracic lesion. Treatment is surgical resection. CONCLUSIONS: Our patient had a successful brachial plexus exploration and dissection of thoracic inlet tumor resected through VATS. Afterwards she had no more signs of Horner's syndrome. Reference #1: Angelopoulos, E., Eleftheriou, K., Kyriakopoulos, G., Athanassiadi, K., Rontogianni, D. and Routsi, C. (2016). A Giant Intrathoracic Malignant Schwannoma Causing Respiratory Failure in a Patient without von Recklinghausen’s Disease. Case Reports in Medicine, 2016, pp.1-3. Reference #2: Ritz, R., Pehl, A., Bartsch, D. and Kirschbaum, A. (2013). Giant Intrathoracic Left-Sided Vagal Schwannoma. The Thoracic and Cardiovascular Surgeon Reports, 02(01), pp.019-022. doi: 10.1055/s-0033-1337368 Reference #3: Torpiano, P., Borg, E., Cassar, P. and Manche', A. (2013). Intrathoracic schwannoma with Horner syndrome. Case Reports, 2013(dec06 1), doi: bcr2013201247. DISCLOSURES: No relevant relationships by Apurwa Karki, source=Web Response No relevant relationships by Salman Khan, source=Web Response No relevant relationships by Nathaniel McElhaney, source=Web Response No relevant relationships by Mahin Rehman, source=Web Response No relevant relationships by FARAZ Siddiqui, source=Web Response