Cytomorphologic features of the plasmacytoid variant of urothelial carcinoma: a case report.

The plasmacytoid variant of urothelial carcinoma is an uncommon form of urothelial carcinoma with a distinctive histologic appearance. Descriptions of the cytologic features of this particular type of urothelial carcinoma in urinary specimens are limited. The present report details the urinary cytomorphologic findings of a plasmacytoid urothelial carcinoma occurring in the urinary bladder of a 66-year-old male. Bladder washings showed the presence of scattered dyscohesive cells with a plasmacytoid appearance characterized by abundant amounts of cytoplasm, eccentrically located nuclei, and inconspicuous nucleoli. The diagnosis of plasmacytoid urothelial carcinoma was confirmed upon histologic examination of a concurrently performed transurethral resection specimen, with immunohistochemical studies supporting this interpretation. Although rare, the plasmacytoid variant of urothelial carcinoma should be a diagnostic consideration when atypical cells with plasmacytoid features are encountered in a urinary specimen.