Clinical management and survival outcomes of patients withdifferent molecular subtypes of diffuse gliomas in China(2011–2017):a multicenter retrospective study from CGGA

Objective:We aimed to summarize the clinicopathological characteristics and prognostic features of various molecular subtypes of diffuse gliomas(DGs)in the Chinese population.Methods:In total,1,418 patients diagnosed with DG between 2011 and 2017 were classified into 5 molecular subtypes according to the 2016 WHO classification of central nervous system tumors.The IDH mutation status was determined by immunohistochemistry and/or DNA sequencing,and 1p/19q codeletion was detected with fluorescence in situ hybridization.The median clinical follow-up time was 1,076 days.T-tests and chi-square tests were used to compare clinicopathological characteristics.Kaplan‒Meier and Cox regression methods were used to evaluate prognostic factors.Results:Our cohort included 15.5%lower-grade gliomas,IDH-mutant and 1p/19q-codeleted(LGG-IDHm-1p/19q);18.1%lowergrade gliomas,IDH-mutant(LGG-IDHm);13.1%lower-grade gliomas,IDH-wildtype(LGG-IDHwt);36.1%glioblastoma,IDHwildtype(GBM-IDHwt);and 17.2%glioblastoma,IDH-mutant(GBM-IDHm).Approximately 63.3%of the enrolled primary gliomas,and the median overall survival times for LGG-IDHm,LGG-IDHwt,GBM-IDHwt,and GBM-IDHm subtypes were 75.97,34.47,11.57,and 15.17 months,respectively.The 5-year survival rate of LGG-IDHm-1p/19q was 76.54%.We observed a significant association between high resection rate and favorable survival outcomes across all subtypes of primary tumors.We also observed a significant role of chemotherapy in prolonging overall survival for GBM-IDHwt and GBM-IDHm,and in prolonging post-relapse survival for the 2 recurrent GBM subtypes.Conclusions:By controlling for molecular subtypes,we found that resection rate and chemotherapy were 2 prognostic factors associated with survival outcomes in a Chinese cohort with DG.