this is are H&E slides of a cell block from the pleural fluid of a 61/F presenting with masses in the mediastinum and right lung. microscopic examination shows medium to large, cohesive, epithelioid cells with vesicular nuclei, prominent nucleoli and eosinophilic cytoplasm. also seen are frequent mitotic figures. DIAGNOSIS: LYMPHOEPITHELIOMA-LIKE THYMIC CARCINOMA *** this is classified as a type of poorly-differentiated squamous cell carcinoma*** *** currently performing CKAE and CD3 for further evaluation ***