Reoperation and radiotherapy improve overall survival in patients with epithelioid glioblastoma : A multi-institutional experience

Epithelioid glioblastoma (Ep-GBM) is a rare variant of glioblastoma characterized by a high recurrence rate and poor prognosis. Currently, there is no established standard treatment for Ep-GBM. Therefore, we identified 58 epithelioid glioblastoma cases to investigate these characteristics and identify the possible prognostic factors of survival. The study encompassed 58 patients with a mean age of 37.6±16.3 years. Gross total resection(GTR) was found to be associated with a longer median PFS compared to partial resection (PR) ( P =0.017). Univariate analysis demonstrated that individuals who received more than six cycles of adjuvant chemotherapy with temozolomide (TMZ) had a longer median PFS ( P =0.009, hazard ratio [HR]=0.404, 95% confidence interval [CI], 0.204-0.799) or OS ( P =0.020, HR=0.408, 95% CI, 0.192-0.868) than those who received fewer cycles. GTR remained significantly associated with PFS ( P =0.021, HR=0.430, 95% CI, 0.210-0.878). Additionally, patients who received radiotherapy had a significantly higher median OS than those who did not ( P < 0.001, HR=0.200, 95% CI, 0.081-0.495). In the multivariate analysis, radiotherapy remained significantly associated with improved survival ( P =0.001, HR=0.181, 95% CI, 0.065-0.502). Patients who underwent reoperation had significantly longer survival than those who did not ( P =0.003, HR=0.268, 95% CI, 0.113-0.633). Multivariate analysis confirmed an association between reoperation and prolonged survival ( P =0.009, HR=0.286, 95% CI, 0.110-0.747). In conclusion, gross total resection, radiotherapy, and adjuvant chemotherapy using TMZ enhanced PFS or OS, reoperation and simultaneous chemoradiotherapy show promise in extending the survival duration of patients with recurrent Ep-GBM.