A RARE CASE OF SOLITARY FIBROUS TUMOR OF THE LUNG PRESENTING WITH CAVITARY LESION AND THROMBOEMBOLISM

Abstract

SESSION TITLE: Lung Cancer 2 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Solitary fibrous tumors (SFT) are fibroblastic mesenchymal tumors that most commonly develop in lungs and pleura. The majority are benign and do not invade or metastasize. CASE PRESENTATION: A 60-year-old male was admitted with cough, sputum production, night sweats, and progressive right leg edema and erythema of 14 days duration. Patient denied fever, chills, anorexia or weight loss. At admission, vital signs were stable. Patient had leukocytosis, normocytic normochromic anemia, normal LDH and haptoglobin, thrombocytosis with 619K platelets. He had elevated PTT 33.6, normal PT/INR. FOBT was negative. Chest x-ray showed right lung apical cavitary lesion which was not present on CXR done three years ago. Patient was a heavy smoker. He denied history of incarceration, sick contacts, recent surgery, immobilization, long flights or car rides. Lower extremity venous doppler showed right popliteal and femoral DVT. CT angiography was negative for PE but showed an irregular cavitary lesion in the right upper lobe with surrounding nonspecific opacities and bilateral hyperinflation. CT abdomen was negative for masses or hepatosplenomegaly. Blood cultures, three acid-fast smears, quantiferon TB, West Nile virus, HIV, hepatitis B and C were negative. Bronchoscopy and broncho-alveolar lavage (BAL) showed 400 WBCs, mainly lymphocytes. Two BAL cultures were negative for bacterial or fungal growth and cytology was negative for malignancy. CT-guided biopsy of the right upper lobe was consistent with SFT: immunoperoxidase stains for pancytokeratin, CK5/6, calretinin, CD34, WT1 and CD99 showed dense fibroblastic proliferation, scattered cytokeratin positive cells, maturity subset stromal and spindle cells without malignant features. Patient was planned for surgical resection of the tumor. DISCUSSION: Patients with SFTs are either asymptomatic or present with non-specific symptoms such as cough, chest pain, dyspnea, and rarely hemoptysis and mass effect. Paraneoplastic symptoms, specifically hypoglycemia, digital clubbing, and hypertrophic pulmonary osteoarthropathy can develop. SFTs typically present as homogeneous masses on CT scans, but cystic masses have been reported. Reports of cavitary SFT as we described in our patient are extremely rare. To our knowledge, there are no reports of SFT cases with paraneoplastic hypercoagulability syndromes. Since regardless of the histologic type the behavior of these tumors is often unpredictable and approximately 10-20% recur or metastasize, surgical resection is recommended. CONCLUSIONS: We presented a case report of a patient who developed cavitary pulmonary SFT accompanied by thrombocytosis and paraneoplastic hypercoagulability syndrome leading to DVT. Clinicians should consider the diagnosis of SFT in patients with similar unusual presentations and plan for early surgical removal of the tumor to reduce the likelihood of recurrence and metastases. Reference #1: Chick, J.F.B., Chauhan, N.R. and Madan, R., 2013. Solitary fibrous tumors of the thorax: nomenclature, epidemiology, radiologic and pathologic findings, differential diagnoses, and management. American Journal of Roentgenology, 200(3), pp.W238-W248. Reference #2: van Houdt, W.J., Westerveld, C.M., Vrijenhoek, J.E., van Gorp, J., van Coevorden, F., Verhoef, C. and van Dalen, T., 2013. Prognosis of solitary fibrous tumors: a multicenter study. Annals of surgical oncology, 20(13), pp.4090-4095. Reference #3: Tay, C.K.J., Teoh, H.L. and Su, S., 2015. A common problem in the elderly with an uncommon cause: hypoglycaemia secondary to the Doege-Potter syndrome. BMJ case reports, 2015, p.bcr2014207995. DISCLOSURES: No relevant relationships by Alexander Goldstein, source=Web Response No relevant relationships by ASM ISLAM, source=Web Response No relevant relationships by Phyo Kyaw, source=Web Response No relevant relationships by Lusine Nahapetyan, source=Web Response No relevant relationships by AHMED TAHA, source=Web Response