Forest plots of the data for four biomarker-outcome comparisons for which eligible data were presented in ten or more studies. Forest plots of HR for OS of (A) VEGF, (B) cyclin D1, (C) p53 and (D) E-cadherin. For each study, the hazard ratio (HR), 95% confidence interval (CI), and relative weight are show. Combined fixed effect HRs and tests for heterogeneity (I2) were based on the generic inverse variance (I-V) method. Combined random effect HRs were calculated according to the DerSimonian-Laird (D + L) method.