A Study of Pemetrexed in Children With Recurrent Cancer

Inclusion Criteria:

   - Patients must have osteosarcoma, Ewing's sarcoma, medulloblastoma, neuroblastoma,
   rhabdomyosarcoma, ependymoma or high-grade non-brainstem glioma

   - Measurable disease

   - Eastern Cooperative Oncology Group (ECOG) performance 0,1,2

   - Adequate renal, liver and bone marrow function

   - Patient's current disease state must be one with no known curative therapy or therapy
   proven to prolong survival with an acceptable quality of life

Exclusion Criteria:

   - Growth factors that support platelet or white cell number or function must not have
   been administered within the last 7 days prior to enrollment (14 days if Neulasta)

   - Patients with central nervous system (CNS) tumors who have not been on a stable or
   decreasing dose of dexamethasone or other corticosteroid for 7 days prior to
   enrollment

   - Patients with uncontrolled infection

   - Patients who have received pemetrexed previously

   - Patients with pleural effusions or ascites