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

Kim, Lucia; Song, Joo Young; Choi, Suk Jin; Park, In Suh; Han, Jee Young; Kim, Joon Mee; Chu, Young Chae

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.