Participants will be randomly assigned with equal probability to one of two dosing groups of lenalidomide. neither the doctor nor the participant will be able to choose which dose is received. eligibility restrictions and the use of stratification will ensure that similar patient populations are being compared, and the number of patients required for the study will increase the certainty that any differences in outcome or side effects are indeed due to the dose received.
* arm a: Treatment with a low dose of lenalidomide Participants will receive a low dose of the study drug by mouth. The dose is 20 mg/m2/day. Meters squared (m2) is determined by the subject's body surface area.
* arm B: Treatment with a high dose of lenalidomide Participants will receive a high dose of the study drug by mouth. The dose is 115 mg/m2/day. Meters squared (m2) is determined by the subject's
body surface area.
all participants will receive treatment in cycles that last 4 weeks (or 28 days) each. During each cycle, participants will take lenalidomide for 21 days and then have a 7-day rest. evaluations will be performed after every 2 cycles of treatment during the first 13 cycles, and then after every 3 cycles for cycles 14-26. Participants may receive up to 26 cycles of treatment on this study as long as their tumor is shrinking or staying the same size and they are not experiencing bad side effects.
* Less than 22 years of age at the time of enrollment
* Body Surface Area >= 0.4 m2 at the time of study enrollment
* Confirmed diagnosis of pilocytic astrocytoma or optic pathway glioma that has relapsed, progressed or become refractory to conventional therapy
* Measurable residual disease
* Lansky or Karnofsky performance status score of >= 60%
* Treated with two or fewer anti-cancer regimens. At least one prior
treatment regimen must have included carboplatin.
* Recovered from the acute toxic effects of all prior treatment prior to
entering this study, with the exception of alopecia, weight changes and
Grade II lymphopenia.
* No growth factors within 2 weeks of entry onto this study
* If taking steroids, must be on a stable or decreasing dose for at least 1
week prior to baseline MRI
* Adequate organ function as defined by protocol
* Must be able to swallow intact capsules