Vorinostat and Temozolomide in Treating Young Patients With Relapsed or Refractory Primary Brain Tumors or Spinal Cord Tumors

Inclusion Criteria: * Histologically confirmed CNS malignancy at original diagnosis or relapse * Histologic confirmation not required for patients with intrinsic brain stem tumors, optic pathway gliomas, or pineal tumors provided CSF or serum tumor markers, including alpha-fetoprotein orbeta-HCG, are elevated * Recurrent or refractory spinal cord tumors allowed * Measurable or evaluable disease * No known curative therapy or therapy proven to prolong survival with an acceptable quality of life * Karnofsky performance status (PS) 50-100% (for patients \> 16 years of age) OR Lansky PS 50-100% (for patients ≤ 16 years of age) * Neurological deficits must have been relatively stable for ≥ 1 week before study entry * Patients unable to walk due to paralysis, but who are up in a wheelchair, are considered ambulatory for the purpose of assessing performance status * ANC ≥ 1,000/μL * Platelet count ≥ 100,000/μL (transfusion independent, defined as no platelet transfusion within the past 7 days) * Hemoglobin ≥ 8.0 g/dL (RBC transfusions allowed) * Creatinine clearance or radioisotope GFR ≥ 70mL/min OR maximum serum creatinine based on age and/or gender as follows: * 0.6 mg/dL (1 year of age) * 0.8 mg/dL (2 to 5 years of age) * 1.0 mg/dL (6 to 9 years of age) * 1.2 mg/dL (10 to 12 years of age) * 1.5 mg/dL (males) or 1.4 mg/dL (females) (13 to 15 years of age) * 1.7 mg/dL (males) or 1.4 mg/dL (females) (≥ 16 years of age) * Bilirubin ≤ 1.5 times upper limit of n…