Hypofractionated conformal radiotherapy for pediatric diffuse intrinsic pontine glioma (DIPG): a randomized controlled trial

Abstract

Background: The pediatric diffuse intrinsic pontine glioma (DIPG) outcome remains dismal despite multiple therapeutic attempts.

Purpose: To compare the results of treatment of pediatric diffuse intrinsic pontine glioma (DIPG) using hypofractionated versus conventional radiotherapy.

Patients and methods: Seventy-one newly diagnosed DIPG children were randomized into hypofractionated (HF) (39Gy/13 fractions in 2.6weeks) and conventional (CF) arm (54Gy/30 fractions in 6weeks).

Results: The median and one-year overall survival (OS) was 7.8months and 36.4±8.2% for the hypofractionated arm, and 9.5 and 26.2±7.4% for the conventional arm respectively. The 18-month OS difference was 2.2%. The OS hazard ratio (HR) was 1.14 (95% CI: 0.70-1.89) (p=0.59). The hypofractionated arm had a median and one-year progression-free survival (PFS) of 6.6months and 22.5±7.1%, compared to 7.3 and 17.9±7.1% for the conventional arm. The PFS HR was 1.10 (95% CI: 0.67-1.90) (p=0.71). The 18-month PFS difference was 1.1%. These differences exceed the non-inferiority margin. The immediate and delayed side effects were not different in the 2 arms.

Conclusions: Hypofractionated radiotherapy offers lesser burden on the patients, their families and the treating departments, with nearly comparable results to conventional fractionation, though not fulfilling the non-inferiority assumption.

Trial registration: ClinicalTrials.gov NCT01635140.

Keywords: DIPG; Diffuse intrinsic pontine glioma; Hypofractionation; Overall and progression-free survival.