Metastatic transitional cell carcinoma causing a unilateral pleural effusion: a case report.

Background: Transitional cell carcinoma (TCC) is a common neoplasm, but it is only rarely associated with serous effusions. The cytologic features of metastatic TCC in pleural effusions have been described only in occasional studies. One feature that raises the possibility of metastatic TCC in this setting is the presence of eosinophilic cytoplasmic inclusions (ECIs).