DIPG-47. RE-IRRADIATION FOR RECURRENT DIFFUSE INTRINSIC PONTINE GLIOMA

The prognosis of diffuse intrinsic pontine glioma (DIPG) remains dismal. The only effective treatment is radiation therapy so far. Nevertheless, the therapeutic effect of radiation therapy doesn’t last for long and almost all the patients experience relapse after several months. Recently, re-irradiation for relapsed DIPG was attempted and showed some benefit for those patients. We retrospective reviewed the efficacy and safety of re-irradiation therapy for five DIPG cases from April 2013 to December 2017. Five patients include three boys and two girls, their mean age was 7.2 years old (4–12). One case only did biopsy for diagnosis, others diagnosed clinically. One case underwent ventricular Ommaya reservoir insertion due to hydrocephalus. Radiation doses were from 19.8Gy to 50.4Gy(1.8–3.0Gy/Fr). The median duration between diagnosis and recurrence was 7.5 months (4–10 months), and the mean survival after the re-irradiation was 6.3 months (two of them still surviving). All five patients completed the treatment without acute toxicity, and four out of five patients demonstrated some improvement of their symptoms which occurred at the recurrence. It has been suggested that re-irradiation might be an effective and safe treatment for selected patients with recurrent DIPG.