- Karnofsky performance score ≥50 for participants>16 year of age and Lansky play score ≥50 for participants ≤16 years of age. Neurologic deficits in participants with CNS tumors must have been relatively stable for at least 7 days prior to study enrollment. Participants who are unable to walk because of paralysis, but who are up in a wheelchair, will be considered ambulatory for the purpose of assessing the performance score