A Study Assessing if it is Safe and Possible to Treat Brain Cancer Patients With Immunotherapy Before They Receive the Standard Treatment.

This study is testing whether giving an immune-boosting drug called ipilimumab (a type of immunotherapy) before standard surgery and radiation for newly diagnosed glioblastoma (an aggressive brain tumor) is safe and feasible — with the hope that priming the immune system early may improve outcomes. **You may be eligible if...** - You are 18 or older - You have a newly diagnosed glioblastoma (a type of aggressive brain tumor) confirmed by imaging or biopsy - Your tumor is located in the upper part of the brain (supratentorial) - You are in good enough health (ECOG 0-1) to receive immunotherapy followed by standard treatment - Your blood counts, liver, kidney, and heart function are adequate **You may NOT be eligible if...** - You have had prior brain tumor treatment - You have active autoimmune disease - You are on steroids at a dose that would suppress the immune response - Your overall health condition makes this combination treatment unsafe Talk to your doctor to see if this trial is right for you.