The pooled HRs, 95% CIs and p values of overall survival and recurrence-free survival stratified by ethnicity, main pathologic type, categories of malignant diseases and detected samples.

N, number of studies; HR, hazard ratio; CI, confidence interval. a, the HRs and 95% CIs of enrolled studies are pooled by the fixed-effects model; b, the HRs and 95% CIs of enrolled studies are pooled by the random-effects model if p value for heterogeneity test was less than 0.10 or I2 was more than 50%.