Cytopathological features of villous adenoma of the urinary bladder in urine: A rare case report.

Villous adenoma of the urinary bladder is a rare tumor that histologically mimics its enteric counterpart. Patients with an isolated villous adenoma have an excellent prognosis, but associated adenocarcinomas can frequently be identified in them as well. There is no literature that discusses the cytopathologic features of villous adenoma. Here we report a case which was diagnosed as villous adenoma histologically, which has been followed up with urine cytology. In urine cytology, many mucin producing cells are recognized. Few cell clusters show glandular formation or arrangement along the basement membrane. When glandular cells with columnar mucin-filled goblet cells are seen in urine cytology, the presence of a primary glandular lesion of the urinary bladder, such as villous adenoma, should be considered possible. Diagn. Cytopathol. 2016;44:632-635.