The prognostic value of CD133 expression in non-small cell lung cancer: a meta-analysis.

CD133 has been identified as a potential cancer stem cell (CSC) marker in non-small cell lung cancer (NSCLC). However, the clinical and prognostic significance of CD133 in NSCLC remains controversial. In this study, a meta-analysis with a total number of 13 studies was performed to clarify the association between CD133 expression and clinical outcomes in publications up to June 2013. Odds ratios (ORs) and their 95 % confidence intervals (CIs) were used to assess the association between CD133 expression and the clinicopathological characteristics of NSCLC. Hazard ratios (HRs) and their 95 % CI were used to quantify the predictive ability of CD133 on NSCLC prognosis. Analysis of these data showed that CD133 expression was not associated with any clinicopathological parameters except for histology (pooled OR = 1.35, 95%CI = 1.04-1.76, P = 0.024) and tumor differentiation (pooled OR = 3.19, 95%CI = 1.10-9.21, P = 0.032). Simultaneously, we also found that positive CD133 expression was not associated with disease-free survival (DFS) (pooled HR = 1.76, 95 % CI = 0.87-3.57, P = 0.114, random-effect) but was associated with overall survival (OS) (pooled HR = 2.06, 95 % CI = 1.08-3.91, P = 0.027, random-effect). Overall, it is appropriate to regard CD133 expression as a potential prognostic factor for the OS of NSCLC patients.