Background: Glioblastoma multiform (GBM) is the most common primary malignant brain tumors. Standard management is maximal safe resection followed by concurrent chemoradiotherapy then adjuvant chemotherapy with temozolomide TMZ. Management of GBM patients also involves medical treatment containing corticosteroids that might have direct effects on tumor cell proliferation and apoptosis. We aimed at discussing the clinical relation between corticosteroids usage in GBM patients, overall survival OS, and progression free survival PFS, according to the records from Clinical Oncology Department, Ain Shams University, Cairo, Egypt. Methods: Retrospective analysis was performed on 66 adult patients diagnosed with GBM by surgery or imaging criteria between January 2014 and December 2016. Data analysis was performed on October 2017 to assess the relation between corticosteroid dependence (defined as the failure to withdraw the corticosteroids after their initiation during the treatment with radiotherapy and TMZ) with OS and PFS. Patients were arranged in 2 arms according to steroid dependency. Arm (A) was steroid dependent (34 patients) and arm (B) was steroid non-dependent (32 patients). Results: The median age of the entire cohort was 52.8 years (Range 25-72) with male predominance (68.1%) and 72.7 % of the patients received radiotherapy as their main treatment. 59.1 % of the whole cohort were treated by standard radiotherapy regimen of 60 Gy, while 13.6 % were treated by hypo-fractionation radiotherapy with total dose of 45 Gy. 62.1 % of the patients received TMZ concurrently with radiotherapy. Corticosteroids dependency was statistically significantly correlated to both OS with a median of 2.5 months in the corticosteroids dependent group vs. 13.1 months in the corticosteroids non-dependent group (p < 0.001), and also to PFS with a median of 2.3 in the corticosteroids dependent group vs. 9.4 months in the corticosteroid non- dependent group (p = 0.035). Conclusions: This study from an Egyptian center shows that dependence on corticosteroids during the course of treatment of GBM patients may affect survival. Larger multicentric studies are needed to elaborate the influence of corticosteroids on the disease course. Legal entity responsible for the study: Clinical Oncology Department, Ain Shams University, Cairo, Egypt. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.