Cilengitide in Combination With Irradiation in Children With Diffuse Intrinsic Pontine Glioma

Inclusion Criteria: * Histologically confirmed diffuse intrinsic pontine glioma * Metastatic disease allowed * MRI measurable disease according to the WHO criteria and for extension cohort * Patient is able to undergo functional MRI (diffusion, perfusion, spectro) * Patient is able to undergo FDG-PET and sestamibi SPECT * Life expectancy \> 8 weeks after the start of study treatment. * No prior chemotherapy for the present cancer; no treatment for any other cancer during the last 5 years. * No prior cerebral radiation therapy * Age \> 6 months and \< 21 years * Lansky Play Scale \> 50 or ECOG Performance Status \< 2; NB: Children and young adults with a worse performance status due to glioma-related motor paresis can be included. * Absolute neutrophils count \> 1.5 x 109/l, Platelets \> 100 x 109/l * Total bilirubin \< 1,5 x ULN, AST and ALT\< 2,5 x ULN * Serum creatinine ≤ 1,5 X ULN for age. If serum creatinine \> 1,5 ULN, creatinine clearance must be \> 70 ml/min/1.73 m² (EDTA radioisotope GFR or 24 hours urines collection) * Normal coagulation tests : prothrombin rate (prothrombin time = PT), TCA (PTT), fibrinogen * No current organ toxicity \> grade 2 according to the NCICTCAE version 4.0, especially cardiovascular or renal disease (nephrotic syndrome, glomerulopathy, uncontrolled high blood pressure despite adequate treatment). In case of known or possible cardiac disease, a cardiological advice will be required prior to the inclusion in the study * If anticonvulsants are currently administered, the dosing regimen must be stable within 1 week prior to the first dose of Cilengitide * If corticosteroids are administered, the dosing regimen must be stable ≥ 5 days prior to the first dose of Cilengitide. * Effective contraception for patients (male and female) of reproductive potential during their entire participation in the study and during 6 months after the last administration of Cilengitide. * Negative pregnancy test (serum beta-HCG) within 1 week prior to start of study treatment in females of reproductive potential * Patient covered by government health insurance * Written informed consent given by patient and/or parents/ guardians prior to the study participation Exclusion Criteria: * Inclusion criteria failure * History of coagulation disorder associated with bleeding or recurrent thrombotic events. * Prior anti-angiogenic therapy * Any other concomitant anti-cancer treatment not foreseen by this protocol. * Concomitant inclusion in another therapeutic clinical trial; participation in another therapeutic clinical trial during the last 30 days. * Pregnancy or breast feeding woman * Uncontrolled intercurrent illness or active infection * Unable for medical follow-up (geographic, social or mental reasons)