Diagnostic significance of dual immunocytochemical staining of p53/cytokeratin20 on liquid-based urine cytology to detect urothelial carcinoma

BACKGROUND: Urine cytology is a noninvasive and inexpensive method; however, it is limited in low sensitivity for detecting and monitoring urothelial carcinoma (UC). To overcome limitation of cytology, several tests using urine samples have been attempted that immunocytochemical staining is an inexpensive and easy to perform ancillary technique. Dual immunocytochemical staining for p53 and cytokeratin 20 (CK20) is assessed in liquid-based urine cytology slides. MATERIALS AND METHODS: Liquid-based urine cytology samples collected between 2008 and 2013 and matched follow-up biopsy samples of high-grade UC (HGUC) (n = 44) and low-grade UC (LGUC) (n = 14) were analyzed. RESULTS: Urine cytology showing atypical cells was subjected to dual-color immunostaining for p53 and CK20. The sensitivity of urine cytology combined with p53 and CK20 immunostaining was 77.3% in HGUC and 52.9% in LGUC. Of 20 cases diagnosed with atypia by urine cytology, 13 (65%) were positive for p53 or CK20. Dual immunocytochemical staining for p53/CK20 improved the diagnostic accuracy of urine cytology. CONCLUSIONS: The present results indicate that cytomorphology combined with p53/CK20 immunostaining is useful for the detection of HGUC and LGUC.