Morphologic features of prostatic adenocarcinoma on ThinPrep® urinary cytology.

Malignant cells of prostatic adenocarcinoma are rarely identified in urine. In most cases, this finding is associated with high stage tumor. Numerous descriptions of the morphology of prostatic adenocarcinoma have been reported using cytocentrifugated specimens. However, no specific morphologic description of prostatic adenocarcinoma in urine using liquid-based cytology has been previously described. Four cases of prostatic adenocarcinoma in urine using ThinPrep® liquid-based preparations were identified between 2002 and 2009 at the University of Wisconsin Hospital and Clinics. Three patients had either high stage tumor or metastatic disease at the time of diagnosis, while the remaining patient had low stage tumor. The morphology of each case was evaluated with specific attention to cell size, nuclear characteristics, nuclear to cytoplasmic ratio, and cytoplasmic characteristics. The resulting key features for prostatic adenocarcinoma in urine are clustering, increased nuclear to cytoplasmic ratio, and prominent nucleoli. Though typically the presence of prostatic adenocarcinoma in urine implies high stage tumor, cells of lower stage tumors may be seen in urine as well.