Hypofractionated radiotherapy in children with diffuse intrinsic pontine glioma

Abstract

Background: Overall survival (OS) of patients with diffuse intrinsic pontine glioma (DIPG) is poor, with radiation therapy (RT) the only intervention that transiently delays tumor progression. Hypofractionated RT and re-irradiation at first progression have gained popularity in improving the quality of life of such patients. Methods: We performed a retrospective review of children with DIPG treated at Kanagawa Children's Medical Center from 2000 to 2018.Results: A total of 24 cases were reviewed. Median age at diagnosis was 6.3 years (1.6-14.0). Twenty patients received RT only once. Thirteen patients received conventionally fractionated RT, and seven patients received hypofractionated RT as up-front RT. Severe toxicities were not observed in patients who received hypofractionated RT. Median OS and time to progression were similar between conventionally fractionated and hypofractionated RT groups.(9.7 [95% confidence interval(CI): 7.1-11.2] versus 11.0[95% CI: 5.2-13.6] months, P = 0.60; 4.2[95% CI: 1.8-8.3] versus 7.1 [95% CI:4.5-8.7] months, P = 0.38). Four patients received re-irradiation at first progression and all patients showed transient neurological improvement and survival more than a year after diagnosis. A 4-year-old boy was re-irradiated 5-and-a-half months after the first re-irradiation; following transient neurological improvement. He survived a further 5 months. Conclusion: Hypofractionated RT for children with newly diagnosed DIPG is well tolerated and feasible from the viewpoint of reducing a patient's burden of treatment. Re-irradiation at first progression is suggested to be beneficial.

Hypofractionated radiotherapy versus conventional radiotherapy for diffuse intrinsic pontine glioma

“…Thus, the meta-analysis ultimately included data from 4 articles (Table 1 ). [ 10 , 11 , 7 , 8 ] Two studies were randomized controlled trials [ 11 , 8 ] and 2 were retrospective studies, [ 10 , 7 ] that included one matched cohort analysis. [ 7 ] The eligible reports were published during 2013 to 2020.…”

“…Zaghloul et al [ 8 ] reported various acute toxicities in the 2 groups, which included skin reactions, hearing issues, decreased appetite, dysphagia, fatigue, insomnia, nightmares, and seizure, although there were no significant differences between the HFRT and CFRT groups. Other studies [ 10 , 11 , 7 ] failed to identify any grade 3–4 radiotherapy-related acute toxicities in patients who underwent HFRT, and the HFRT and CFRT strategies appeared to provide a similar efficacy. Zaghloul et al [ 8 ] evaluated steroid discontinuation, which occurred in 6 HFRT cases and 5 CFRT cases, and also noted that the HFRT group exhibited significant improvements in neurologic conditions (cranial nerve disorders and ataxia).…”

“…[ 7 , 8 ] However, 2 related reports were published in 2020, which facilitated our meta-analysis of the outcomes after HFRT and CFRT. [ 10 , 11 ]…”

A New Treatment Opportunity for DIPG and Diffuse Midline Gliomas: 5-ALA Augmented Irradiation, the 5aai Regimen

“…Irradiation at~1.25 MeV is the mainstay of current DIPG treatment [1,7]. After initial intensity-modulated conformal radiation of 54-60 Gy delivered in~2.0 Gy fractions, DIPG median survival remained 12 to 16 months.…”

“…After initial intensity-modulated conformal radiation of 54-60 Gy delivered in~2.0 Gy fractions, DIPG median survival remained 12 to 16 months. A second, lower dose of irradiation is possible, but does not substantially change outcome [7,8]. MRI fiber tractography of corticospinal tracts show that re-irradiation can diminish DIPG infiltration, displacement, and tract disruption with corresponding improved temporary functioning, even when overall survival is not prolonged.…”