Neurological Symptom Improvement After Re-Irradiation in Patients With Diffuse Intrinsic Pontine Glioma: A Retrospective Analysis of the SIOP-E-HGG/DIPG Project

Abstract

PurposeThe aim of this study is to investigate the spectrum of neurological triad improvement in patients with diffuse intrinsic pontine glioma (DIPG) treated by re-irradiation (re-RT) at first progression.MethodsWe carried out a re-analysis of the SIOP-E retrospective DIPG cohort by investigating the clinical benefits after re-RT with a focus on the neurological triad (cranial nerve deficits, ataxia, and long tract signs). Patients were categorized as “responding” or “non-responding” to re-RT. To assess the interdependence between patients’ characteristics and clinical benefits, we used a chi-square or Fisher’s exact test. Survival according to clinical response to re-RT was calculated by the Kaplan–Meier method.ResultsAs earlier reported, 77% (n = 24/31) of patients had any clinical benefit after re-RT. Among 25/31 well-documented patients, 44% (n = 11/25) had improvement in cranial nerve palsies, 40% (n = 10/25) had improvement in long-tract signs, and 44% (11/25) had improvement in cerebellar signs. Clinical benefits were observed in at least 1, 2, or 3 out of 3 symptoms of the DIPG triad, in 64%, 40%, and 24%, respectively. Patients irradiated with a dose ≥20 Gy versus <20 Gy may improve slightly better with regard to ataxia (67% versus 23%; p-value = 0.028). The survival from the start of re-RT to death was not different between responding and non-responding DIPG patients (p-value = 0.871).ConclusionA median re-irradiation dose of 20 Gy provides a neurological benefit in two-thirds of patients with an improvement of at least one symptom of the triad. DIPG patients receiving ≥20 Gy appear to improve slightly better with regard to ataxia; however, we need more data to determine whether dose escalation up to 30 Gy provides additional benefits.

Molecular Characterization and Treatment Approaches for Pediatric H3 K27-Altered Diffuse Midline Glioma: Integrated Systematic Review of Individual Clinical Trial Participant Data

“…Therapeutically, only irradiation was found to have a significant benefit on OS. The literature also corroborates this, but the toxicity and poor quality of life associated with repeated radiation and its marginal improvement on OS has made this treatment modality unappealing [ 32 , 33 ]. The use of personalized therapeutic strategies showed a marginal benefit in our analysis, and this is likely the approach that will be needed at a combination level to combat these highly heterogeneous tumors.…”

Hypofractionated re‐irradiation for diffuse intrinsic pontine glioma

“…Previously conducted retrospective and prospective studies detailing reRT are summarized in Table 2. [11][12][13][15][16][17][18][19][20][21][22][23] Median OS has ranged from 4 to 9 months from reRT with a mean of 6.2 months. 8 Longer interval between reRT from initial RT is associated with survival benefit with median 6.4 months OS in patients receiving reRT 6−12 months after the initial RT.…”

“…Our experience showed comparable survival to published series with OS from diagnosis of 18 months and from reRT of 6.9 months. Previously conducted retrospective and prospective studies detailing reRT are summarized in Table 2 11–13,15–23 . Median OS has ranged from 4 to 9 months from reRT with a mean of 6.2 months 8 .…”

Nutritional Support and Prevention of Complications in Treatment Contribute to Improved Prognosis in Pediatric Diffuse Intrinsic Pontine Glioma Patients

“…DIPG, as a common glioma in children, has its uniqueness compared to adult gliomas. This disease cannot be treated surgically, and the currently considered effective method is only radiotherapy, with a short survival period 11 . Because of the special location of DIPG, patients often have symptoms in the early stage of the disease and progress rapidly 6 .…”