Re-Irradiation of Progressive or Recurrent DIPG

Inclusion Criteria:

All of these criteria must be met for a patient to be eligible for this study:

1. Each site may accept a patient on study of any age that they have permission totreat and follow on study per their institutional policy.

2. The patient has no evidence of metastases on cranial or spinal MR imaging

3. The patient has received RT in the past, given to a total cumulative dose of <60 Gy;prior radiation using opposed lateral fields, conformal 3-D fields, IMRT or usingprotons is acceptable

4. At least 180 days have elapsed from the last day of primary RT for DIPG

5. The patient has recovered from all acute and subacute toxicities of prior RT and ofchemotherapy, if chemotherapy was utilized in the past

6. The patient has been off all anti-tumour therapy for at least 14 days

7. The patient has a Lansky score of 40% or higher

8. The patient has a life expectancy anticipated to be at least 8 weeks with treatmentusing re-irradiation, with or without dexamethasone

9. The patient has no uncontrolled medical condition (e.g., seizures, diabetes,infection) that would interfere with the delivery of rRT

10. The patient agrees to not enroll on any other clinical trial of an anti-tumourintervention

11. The patient agrees to report and have recorded the use of all medications takenduring ReRAD therapy, from the time of diagnosis of progression or recurrence, thenthrough and after completion of, ReRAD therapy; this includes the use ofcomplementary, alternative and dietary therapies

12. The patient is treated at a site where the study is approved by the local ethicsboard

13. Males and females of child-bearing potential must agree to use effective birthcontrol measures during rRT

14. Consent, and, if applicable, assent, has been obtained according to institutionalstandards

Exclusion Criteria:

If the patient fulfills any of these criteria, then he or she will not be eligible for the study:

1. Females who are pregnant, due to risks from rRT on the developing fetus.

2. Any patient with a condition that prohibits the planned delivery of rRT asprescribed in this study.

3. Patients who are receiving any other clinical trial of an anti-tumour intervention