Primary lung sarcoma is an extremely rare tumor, accounting for less than 0.5% of all lung tumors. Histological subtypes are differentiated on the basis of immunohistochemical markers, such as vimentin, desmin, actin, CD99, and epithelial membrane antigen. A 50-year-old male presented with progressively increasing shortness of breath with cough for 2 months. On Contrast Enhanced Computed Tomography (CECT) of thorax a large heterogeneous mass with multiple areas of necrosis, occupying almost whole of left hemithorax was seen. CT-guided Fine Needle Aspiration Cytology (FNAC) revealed spindle cell neoplasm. Histopathological examination revealed a spindle cell sarcoma. On immunohistochemistry the tumor cells expressed both epithelial membrane antigen and vimentin. Hence, final impression from immunohistochemistry was primary monophasic synovial sarcoma of lung.
Synovial sarcoma, Lung, EMA