Cytologic Features of Prostatic Adenocarcinoma in Urine: Comparison with Urothelial Carcinoma

ABSTRACT

BACKGROUND: Prostate adenocarcinoma (PACa) cells are rarely identified in urine cytology specimens and might be easily overlooked or misdiagnosed as urothelial neoplasm when clinically unsuspected. METHODS: We reviewed 19 urine cytology specimens obtained from 13 patients with PACa and evaluated the characteristic features discriminating PACa from urothelial carcinoma (UCa). For comparison, 27 cases of high-grade UCa (HGUCa) and 10 cases of urothelial carcinoma in situ (UCis) were also evaluated. RESULTS: The urine cytologic evaluation of PACa revealed clustered cells forming 3-dimensional syncytial fragments with occasional microacinar grouping in a clean background. Most tumor cells were small and uniform with a high nuclear-to-cytoplasmic ratio and indistinct cell borders. The nuclei were round-to-oval and the cytoplasm was scanty and thin. One or more centrally-located prominent nucleoli were characteristically noted in one half of the cases. The nucleoli had a well-defined, large, round and eosinophilic appearance. In four high-grade cases, large tumor cells were encountered and had relatively monotonous cells with smooth-outlined cell clusters, well-defined and thin cytoplasm, and round nuclei with characteristic prominent nucleoli. CONCLUSIONS: Combining the information of prostate cancer and the recognition of cytomorphologic features of PACa will help differentiate PACa from HGUCa and UCis.