Progression-free survival was defined as the time from the initiation of treatment to the earliest date of failure (disease progression, death from any cause, or a second malignancy) or to the last assessment date for patients who did not fail. Disease progression was defined as progressive neurologic abnormalities or worsening neurologic status not explained by causes unrelated to tumor progression (eg, anticonvulsant or corticosteroid toxicity, electrolyte disturbances, sepsis, hyperglycemia, weaning of steroids, radiation necrosis, etc); or a greater than 25% increase in the bi-dimensional measurement of the tumor, as compared with the previous scan; or the appearance of a new lesion; or an increase in the doses of dexamethasone required to maintain stable neurologic status or imaging.