Coexistence of Pulmonary and Mediastinal Epitheloid Hemangioendothelioma- A Rare Tumor with A Rare Presentation

Abstract

Epitheloid hemangioendothelioma (EHE) is a very rare,vascular, low to intermediate grade malignant tumor. It has a predilection for the lungs and liver but may arise from many organs, simultaneously or sequentially. Mediastinal location is extremely rare with no more than 25 cases in the literature. In the present case, we report synchronic lung and mediastinal EHEs which have different histopathologic grades and FDG uptakes. A 49-year-old male patient was admitted to our hospital with respiratory complaints. Computed tomography revealed a left mediastinal tumor and bilateral multipl lung nodules. Positron Emission Tomography scan showed a significant fluorodeoxyglucose (FDG) uptake in the mediastinal mass (SUVmax:9.7) but no significant uptakes in pulmonary nodules. Histopathologic and immunohistochemical analysis were consistent with a low grade EHE for lung nodules and intermediate grade EHE for mediastinal tumor. The patient had chemotherapy postoperatively but died 12 months after the initial diagnosis due to the respiratuary failure. Epitheloid hemangioendothelioma should be kept in mind in the differential diagnosis of synchronic tumors involving lung and mediastinum. It is very difficult in some cases to confirm whether the tumor is a primary, multicentric or metastatic lesion. Clinical behaviour is variable among different cases but prognosis is poor for intermediate grade tumors.