Cyclin-dependent kinase inhibitor p27(Kip1) expression in transitional cell carcinoma of renal pelvis and ureter.

We examined the expression and significance of p27(Kip1) 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 p27(Kip1) labeling index and histologic grade or pathologic stage. Patients with p27(Kip1) labeling indices of 27 or greater had more favorable prognoses in comparison to those with p27(kip1) labeling indices less than 27 (P<0.01). Multivariate analysis indicated that p27(Kip1) had an independent predictive prognostic value (P<0.05). The p27(Kip1) may be a novel prognostic marker for transitional cell carcinoma of the renal pelvis and ureter.