The pooled OR was 1.00, (95% CI = 0.81–1.23, P = 0.99, fixed effect) (Figure 4) and 0.87 (95%CI = 0.61–1.24, P = 0.45, random-effect) (Figure 5), suggesting that CD133 expression was not associated with the histology of adenocarcinoma or squamous carcinoma. This evidence concerns the gene PROM1 and adenocarcinoma.