- Patients must not have progressing or untreated central nervous system (CNS) metastases or leptomeningeal disease; patients with a history of resected brain metastases with stable magnetic resonance imaging (MRI) scans for 3 months including within 4 weeks of study start are eligible; patients with a history of gamma knife radiosurgery or whole brain radiation with stable MRI scans for 3 months including within 4 weeks of study start are eligible