Cyclin-dependent kinase inhibitor p27Kip1 expression in transitional cell carcinoma of renal pelvis and ureter

We examined the expression and significance of p27Kip1 protein in 79 patients with transitional cell carcinoma of the renal pelvis and ureter. Immunohistochemical staining of archival tissue specimens was done using a labeled streptavidin–biotin–peroxidase method. There was no significant association between p27Kip1 labeling index and histologic grade or pathologic stage. Patients with p27Kip1 labeling indices of 27 or greater had more favorable prognoses in comparison to those with p27kip1 labeling indices less than 27 (P<0.01). Multivariate analysis indicated that p27Kip1 had an independent predictive prognostic value (P<0.05). The p27Kip1 may be a novel prognostic marker for transitional cell carcinoma of the renal pelvis and ureter.