Proton Beam Radiotherapy for Pediatric Gliomas: Early Outcomes and Dose Comparison

Koh, Hyeon Kang; Min, Byung Jun; Park, Jeong Hoon; Cho, Kwan Ho; Park, Hyeon Jin; Shin, Sang Hoon; Kim, Joo Young

Abstract

BACKGROUND
Proton beam radiotherapy (PBT) has shown to provide high radiation dose to tumors and to save surrounding normal tissues because of its physical characteristics, Bragg peak. In the current study, we report the early outcomes for pediatric patients with intracranial gliomas treated with PBT and compared PBT plan (pencil beam scanning and double scattering) with intensity modulated radiotherapy (IMRT) plan and three dimensional-conformal radiotherapy (3D-CRT) plan.
METHODS
Clinical data from 18 consecutive children with intracranial gliomas who underwent PBT from May 2007 to April 2012 was collected. The median follow-up duration was 16 months (range 6-69).
RESULTS
There were 9 patients with brain stem glioma, 2 patients with optic pathway glioma, 2 patients with low grade glioma (LGG), 2 patients with anaplastic astrocytoma (AA) and 3 patients with glioblastoma multiforme (GBM). The median overall survival for patients with brain stem glioma was 11 months. Patients with optic pathway glioma, LGG or AA were all alive without progression except one patient. Among patients with GBM, one patient had no evidence of disease 25 months after PBT. When PBT plan was compared to those of IMRT and 3D-CRT for patients with LGG or AA and one patient with brain stem glioma by DVH analysis, PBT showed better sparing effect on normal tissue compared to IMRT and 3D-CRT, especially in low dose area.
CONCLUSION
PBT could be delivered safely and effectively to pediatric patients with gliomas. For confirming the clinical benefits of PBT, further follow-up is necessary.