Uroplakin II is a more sensitive immunohistochemical marker than uroplakin III in urothelial carcinoma and its variants.
OBJECTIVE
Uroplakin (UP) II and UPIII are highly specific immunohistochemical markers for urothelial differentiation. Here we studied the sensitivity of UPII and UPIII in conventional and variant urothelial carcinomas (UCs).


METHODS
Immunohistochemical staining for UPII and UPIII was performed on tissue microarray slides, including 105 conventional bladder UCs (BUCs), 90 upper urinary tract UCs (UUTUCs), and 47 micropapillary, 16 plasmacytoid, 22 small cell carcinoma, and 41 sarcomatoid UC variants.


RESULTS
UPII expression was significantly higher than UPIII expression in conventional BUC (44% vs 17%, P < .001) and UUTUC (67% vs 46%, P = .045). UPIII expression was significantly higher in UUTUC than in BUC (P < .001). In UC variants, UPII expression was significantly higher than UPIII expression in micropapillary (91% vs 25%, P < .001), plasmacytoid (63% vs 6%, P < .001), and sarcomatoid (29% vs 5%, P = .032) variants. Only rare cases of the small cell carcinoma variant had focal UPII and UPIII expression. Compared with conventional UC, the sarcomatoid variant had significantly lower UPII expression, whereas the micropapillary variant had significantly higher UPII expression (P < .001).


CONCLUSIONS
UPII demonstrates a significantly higher sensitivity than UPIII in conventional and variant UCs. Thus, UPII is a more valuable marker than UPIII in immunohistochemical analyses for confirming the urothelial origin of carcinomas.
From the Departments of Pathology and.
Wenping
W
Li
From the Departments of Pathology and.
Yu
Y
Liang
From the Departments of Pathology and.
Michael T
MT
Deavers
Urology, University of Texas MD Anderson Cancer Center, Houston.
Ashish M
AM
Kamat
Urology, University of Texas MD Anderson Cancer Center, Houston.
Surena F
SF
Matin
Urology, University of Texas MD Anderson Cancer Center, Houston.
Colin P
CP
Dinney
From the Departments of Pathology and.
Bogdan
B
Czerniak
From the Departments of Pathology and ccguo@mdanderson.org.
Charles C
CC
Guo
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis* / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D046888:Tissue Array Analysis; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D060170:Uroplakin II / Q000032:analysis / Q000096:biosynthesis*; D060171:Uroplakin III / Q000032:analysis / Q000096:biosynthesis*
D014408:Biomarkers, Tumor; C554658:UPK2 protein, human; C554660:UPK3A protein, human; D060170:Uroplakin II; D060171:Uroplakin III
Uroplakin II; Uroplakin III; Urothelial carcinoma; Urothelial carcinoma variants