- Patients must have a CT or MRI scan of the brain to evaluate for central nervous system (CNS) disease within 42 days prior to step 2 re-registration; patient must not have leptomeningeal disease, spinal cord compression or brain metastases unless: (1) metastases have been locally treated and have remained clinically controlled and asymptomatic for at least 14 days following treatment, AND (2) patient has no residual neurological dysfunction and has been off corticosteroids for at least 1 day prior to re-registration