SESSION TITLE: Disorders of the Pleura 2 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 pm - 02:15 pm INTRODUCTION: Primary tumors of the pleura are rare. Majority of the tumors are benign. About 10–20% of the cases reported in the literature are malignant. We present a case of a patient with non specific symptoms and radiological findings consistent with a mass of pleural origin. CASE PRESENTATION: 44 year old African American male, presented with symptoms of productive cough, fever and left sided pleuritic chest pain since the last two months. He was recently incarcerated and released two weeks prior to presentation. He was a former smoker of 20 pack years. PPD and HIV test done within the last one year were normal. On physical examination, he had a fever of 102.2F, heart rate of 127/min, and respiratory rate 22/min. Chest auscultation revealed bilateral expiratory wheezing. Labs showed a normal complete blood count and metabolic panel. TB Gold quantiferon was less than 0.01 IU/ml. Respiratory virus panel was positive for rhinovirus. Initial Chest X ray showed a relatively well demarcated round mass in the left mid-lung with minimal displacement of the carina to the right. CT Chest confirmed the presence of a 12.0 x 14.6 x 13.1 cm pleural based lung mass with atelectasis of the left upper lobe and mass effect on the left hilar structures. Patient underwent a CT guided biopsy of the mass. Pathology revealed atypical cells with a low to moderate degree of pleomorphism. Immunohistochemistry revealed expression of CD 34 and diffuse nuclear expression of STAT6. Patient underwent surgical resection of the mass with partial pleurectomy. Intraoperative findings revealed large chest wall mass attached to the anterior parietal pleura. Post-operative course was unremarkable. Surgical pathology confirmed the presence of a malignant solitary fibrous tumor. DISCUSSION: Solitary fibrous tumors of the pleura (SFTP) are rare neoplasms of mesenchymal origin believed to arise from sub mesothelial connective tissue. SFTP is common in the fifth and sixth decades of life compared with SFTs arising intra-abdominally or in soft tissue. There is no sexual predilection. Evidence of a genetic predisposition or a relationship to exposure to asbestos or tobacco have not been demonstrated. The most common presenting symptoms are non-specific and include cough, chest pain and dyspnea. Paraneoplastic syndromes may be occur and present with clubbing, pulmonary osteoarthropathy secondary to secretion of hyaluronic acid, and refractory hypoglycemia due to secretion of insulin like growth factor II. Our patient presented with symptoms of an upper respiratory tract viral infection and non specific symptoms consistent with SFTP .Surgical resection is the mainstay of treatment in both benign and malignant variants. CONCLUSIONS: SFTP are rare. They may present with non specific symptoms.The prognosis for patients with SFTP is generally favorable with a 5-year overall survival rate ranging from 79 to 100%. Reference #1: 1. Solitary fibrous tumors of the pleura.Cardillo G1, Lococo F, Carleo F, Martelli M.Curr Opin Pulm Med. 2012 Jul;18(4):339-46. https://doi.org/10.1097/MCP.0b013e328352f696 Reference #2: Solitary fibrous tumor of the pleura.Robinson LA.Cancer Control. 2006 Oct;13(4):264-9 DISCLOSURES: No relevant relationships by MUHAMMAD ADEEL, source=Web Response no disclosure on file for Ashish Arora; No relevant relationships by Bilal Bangash, source=Web Response No relevant relationships by Jeff Kwon, source=Web Response No relevant relationships by Safal Shetty, source=Web Response