The role of p53 on survival of upper urinary tract urothelial carcinoma: A systematic review and meta-analysis

A systematic review and meta-analysis of the published literature that investigated the p53 expression and its effects on upper urinary tract urothelial carcinoma (UUTUC) prognosis was conducted. PubMed, Cochrane Library, OVID, and Scopus databases were searched for bibliographic information of articles about p53 expression evaluated by immunohistochemistry and survival in UUTUC from inception until June 2012. Seven articles met the eligibility criteria for this systematic review. The eligible studies included a total of 514 patients with a mean number of 73.4 patients per study (range, 42-154). None of the 7 included studies were based on the data of prospective analysis of survival. The threshold for dichotomizing the level of p53 also varied widely among studies, from 10% to 50%. When only unadjusted survival data were included, the pooled hazard ratio (HR) was statistically significant for disease-free (pooled HR, 1.70 [95% CI, 1.22-2.38), cancer-specific (pooled HR, 2.11 [95% CI, 1.13-3.93]), and overall survival (pooled HR, 1.55 [95% CI, 1.03-2.35]). There was no between-study heterogeneity in the effect of p53 status on all of the meta-analyses, with a P value >.05 and I² generally toward <50%. There was no clear evidence of funnel plot asymmetry, and no evidence of publication bias was found. Results of the meta-analysis suggest that p53 overexpression might be a prognostic factor for patients with UUTUC. These results need to be further confirmed by an adequately designed prospective study with larger populations.