Abstract
Backgrounds Controversy surrounding CpG island methylator phenotype (CIMP) in glioma exists with regard to its prognostic value.Methods PubMed, EMBASE, and Cochrane Library databases were searched for studies describing molecular and clinicopathological features, and overall survival of gliomas stratified by CIMP status. Associations of CIMP with outcome parameters were estimated using odds ratio (OR) or hazard ratios (HRs) with a 95% confidence interval (CI) using a fixed or random effects model.Results A total of 12 studies involving 2386 gliomas (1051 CIMP-positive and 1335 CIMP-negative) were included. Molecular analysis showed that CIMP is more frequent in IDH1-mutated gliomas (OR 229.07; 95% CI 138.72–378.26) and 1p19q LOH gliomas (OR 5.65; 95% CI 2.66–12.01), though CIMP was not associated with EGFR mutation (OR 0.14; 95% CI 0.05–0.43) or MGMT promoter methylation (OR 3.01; 95% CI 0.79–11.48). Clinicopathological analysis showed that CIMP is more frequent in oligodendroglioma (OR 5.51; 95% CI 3.95–7.70), but less frequent in glioblastoma (OR 0.14; 95% CI 0.10–0.19). However, CIMP was not associated with anaplastic oligoastrocytomas (OR 1.57; 95% CI 1.24-2.00) or oligoastrocytoma (OR 0.79; 95% CI 0.35–1.76). We found that CIMP-positive glioma was associated with a longer overall survival (HR -0.57; 95% CI -0.97– -0.16).Conclusions A CIMP-positive glioma has better prognosis and its own molecular features (such as IDH1 and 1p19q LOH mutations) and clinicopathological features. These conditions suggest CIMP could be used as an independent prognostic marker for glioma.
Meta-analysis of the prognostic value of CpG island methylator phenotype in rectal cancer
