Prognostic value of MCM2 immunoreactivity in stage T1 transitional cell carcinoma of the bladder

Due to the heterogeneous biologic behavior of stage T1 bladder carcinomas, there is a need for new markers allowing to assess the prognosis more accurately. To our knowledge, there are no reports on studies investigating minichromosome maintenance protein 2 (MCM2) expression in bladder carcinomas. Thus, we investigated the prognostic value of MCM2 immunoreactivity in stage T1 bladder tumors.

Fifty-four tumors were analyzed using Biochip microarrays. Also p53 and Ki67 antigen expression were examined. Immunohistochemical scores were compared with the clinical outcome.

During a median follow-up of 43 months, tumor recurrence was registered in 43 and progression to stage T2 in 19 patients. Kaplan-Meier curves demonstrated that high-level MCM2 expression was significantly associated with early tumor recurrence when using a cutoff of 60% (p=0.0035 by log-rank test), and with early tumor progression when using a cutoff of 20% (p=0.0454). There was no relationship (p=0.604) between MCM2 and p53, but a tendentious relationship (p=0.082) between MCM2 and Ki67 antigen expression. MCM2 (p=0.006), Ki67 antigen (p=0.035) and p53 expression (p=0.049) as well as tumor grade (p=0.026) and age (p=0.025) were found significantly associated with recurrence-free survival by univariate Cox regression analysis, among which only Ki67 antigen expression (p=0.015) and age (p=0.019) proved to be of independent predictive value by multivariate analysis. Concerning tumor progression, MCM2 expression was identified as the only predictive parameter by log-rank test, but it was not of independent predictive value by multivariate analysis (p=0.101).

Our data suggest that MCM2 expression may bear some prognostic relevance in stage T1 bladder carcinomas.