- Solid tumor patients must be off corticosteroids prior to registration; if GBM patient is receiving corticosteroids, patient must be on a stable or decreasing dose of corticosteroids for at least 5 days prior to baseline magnetic resonance imaging (MRI) or computed tomography (CT); if steroids are added or the steroids dose is increased between the date of the screening MRI or CT and the start of treatment, a new baseline MRI or CT is required