Background: P53 is the most widely investigated molecular marker in bladder cancer. We aimed to review comprehensively the evidence for use of changes in P53 to predict bladder-cancer recurrence, progression, and mortality.
Methods: We reviewed 168 publications from 117 studies. Estimates of significance were extracted from association tests, and hazard ratios with 95% CI from actuarial curves and Cox regression analyses. A meta-analysis was done on the studies that applied Cox models.
Findings: The methods used to assess significance varied widely between studies. 27% (nine of 34) of studies that assessed the prognostic value of P53 overexpression in recurrence by use of multivariate tests showed a significant association. The corresponding values for progression and mortality were 50% (12 of 24) and 29% (ten of 35), respectively. In the studies that used Cox models, the overall risk of recurrence was 1.6 (95% CI 1.2-2.1), of progression was 3.1 (1.9-4.9), and of mortality was 1.4 (1.2-1.7). These findings could be overestimates because of publication and reporting bias.
Interpretation: After 10 years of research, evidence is not sufficient to conclude whether changes in P53 act as markers of outcome in patients with bladder cancer.