Primary objective : To increase the 3 year progression-free survival from 40% to 60%. Patients included : metastatic, cerebral primitive neuroectodermal tumors in children aged over 5 years.

Inclusion Criteria:

1. Type of tumor:

   • Metastatic medulloblastoma whatever the quality of the initial resection (radiologically visible metastases by MRI and/or CSF invaded by at least one mass of tumoral cells).
   • Incompletely resected local medulloblastoma with a residue > 1.5 cm2.
   • Anaplastic, large cell medulloblastoma whatever the risk criteria (localized or metastatic, complete or incomplete resection).
   • Medulloblastoma with amplification of c-myc or N-myc whatever the risk criteria (local or metastatic, complete or incomplete resection).
   • Local and/or metastatic sustentorial PNET.

2. Age at diagnosis of the medulloblastoma of more than 5 years and less than 20 years.

3. Age at diagnosis of S-PNET of more than 10 years and less than 20 years.

4. Nutritional and general status compatible with treatment, Lansky score > 60.

5. Estimated life expectancy > 1 months.

6. Radiographs must be available for the second reading in dicom format on a CD-ROM.

7. Hematological function at diagnosis: PMN > 1.0 x 109/l and platelets > 100 x 109/l.

8. Hepatic function at diagnosis: serum bilirubin < 1.5 times normal value; ASAT and ALAT < 2.5 times normal values; prothrombin time > 50%; fibrinogen > 1.5 g/l.

9. Renal function at diagnosis: serum creatinine according to age in a correctly hydrated child: 1 to 15 years < 65 micromol/l; 15 to 18 years < 110 micromol/l.

10. No organ toxicity (Grade > 2 according to NCI-CTC coding, version 2.0)

11. No other concomitant anti-cancer treatment.

12. No prior anti-cancer therapy.

13. No prior irradiation.

14. Written informed consent signed by both parents or legal guardians

Exclusion Criteria:

1. Failure to comply with one of the inclusion criteria.
2. Severe or life-threatening infection.
3. Uncontrolled active or symptomatic intracranial hypertension.
4. Refusal of parents or legal guardian.
5. Patients incapable of undergoing medical follow-up for geographical, social or mental reasons