The Effects Of Different Expression States Of MGMT Promoter Methylation On Pseudoprogression Of Glioma:A Systematic Review And Meta-Analysis

Objective: To investigate the difference of the incidence of pseudoprogression in glioblastoma with or without MGMT promoter methylation,and provide help for clinical identification and diagnosis of pseudoprogress of glioma after comprehensive treatment.Methods:We systematically searched databases such as CNKI,WanFang,Pubmed,Cochrane Library,Embase,Web of Science,etc,for the relevant literatures on pseudoprogress of glioma after comprehensive treatment up to December 31,2018.According to specific inclusion and exclusion criteria,literatures were strictly screened,the full texts were read and the data was extracted.The incidence of pseudoprogression was used as the main outcome index,and the incidence of imaging progression was used as the secondary outcome index.Different expression states of MGMT promoter methylation were taken as different exposure factors.Meta-analysis was performed using RevMan5.3 After performing heterogeneityeffect tests,we used the fixed-effect model to evaluate the pooled data.Results:Seven studies were eventually included(N=674 patients),and all patients were pathologically confirmed with glioblastoma.Meta-analysis results were as follows:1.Incidence of pseudoprogression in GBMS : Among patients with imaging progression after comprehensive treatment,the incidence of pseudoprogression was significantly higher in the MGMT promoter methylation group than in the MGMT promoter non-methylation group [RR=2.13 95%CI(1.70,2.68),P < 0.00001];when all patients were included in the analysis after comprehensive treatment,the incidence of pseudoprogression was still significantly higher in the MGMT promoter methylation group than in the MGMT promoter non-methylation group [RR=2.35 95%CI(1.82,3.05),P<0.00001]2.Incidence of glioblastoma imaging progression: The incidence of imaging progression after comprehensive treatment was higher in the MGMT promoter methylated group than in the MGMT promoter non-methylation group [RR=1.21 95%CI(1.02,1.44),P=0.03]3.Incidence of true glioblastoma progression: The incidence of true progression was significantly lower in the MGMT promoter methylation group than in the MGMT promoter non-methylation group [RR=0.54 95%CI(0.37,0.77),P=0.0006]Conclusion:Glioblastoma patients with MGMT promoter methylation are more likely to have pseudoprogression after the comprehensive treatment involving TMZ,and the MGMT promoter methylation is a powerful predictor of pseudoprogression...