2017 Volume 66 Issue 1 Pages 1-7
Reactive urothelial cells (RUCs) in calculi show features of an atypical repair reaction. Therefore, differentiation between RUCs and urothelial carcinoma cells (UCCs) based on morphology alone can be a diagnostic challenge. In this study, we evaluated the diagnostic utility of an anti-vimentin antibody for differentiating RUCs from UCCs. Eighteen calculi patients, 17 urothelial carcinoma patients, and 21 patients without calculi or urothelial carcinoma were examined. Urine cytology slides were prepared using the SurePath™ method, immunoenzyme was stained with the anti-vimentin antibody, and the number of vimentin-positive cell clusters was counted. In terms of vimentin positivity, we comparatively reviewed three items. The first comparison was between RUC and UCC cases. The second comparison was between all cell clusters in RUC and UCC cases. The third comparison was between sites of calculi in RUC cases. In the RUC group, vimentin showed strong staining in 18/18 (100%) cases and 87/202 (43.1%) cell clusters. The UCC group showed positivity for vimentin in 2/17 (11.8%) cases and 2/455 (0.4%) cell clusters. In cases and all cell clusters, the vimentin-positivity rate of RUCs was significantly higher than that of UCCs (p < 0.001). In patients without calculi or urothelial carcinoma, vimentin positivity was found in 2/21 (9.5%) cases and 2/938 (0.2%) cell clusters. In terms of the vimentin-positivity rate of each site in calculi of the RUC group, vimentin was expressed in 34/67 (50.7%) clusters of cells from the renal pelvis and 4/22 (18.2%) clusters of cells from ureter; the renal pelvis had a significantly higher positivity rate (p = 0.007). Our results suggest that the immunoenzyme staining of vimentin in urine cytology can help to distinguish RUCs from UCCs.
