Conventional MRI cannot predict survival in childhood diffuse intrinsic pontine glioma

Abstract

Diffuse intrinsic pontine glioma (DIPG) of childhood has a dismal prognosis. Clinical trials of new agents are vital and it is essential that the correct endpoints and disease assessments are chosen. A retrospective review of magnetic resonance imaging (MRI) scanning in a pure population of DIPG was undertaken. Baseline diagnostic MRI findings included; local tumour extension in upper medulla (74%) or midbrain (62%), metastatic disease (3%), basilar artery encasement (82%), necrosis (33%), intratumoural haemorrhage (26%), hydrocephalus (23%) and dorsal exophytic component (18%). Post-treatment MRI scans demonstrated increases in; leptomeningeal metastatic disease (16%), cystic change/necrosis (48%), enhancement (72%) and intratumoural haemorrhage (32%). Response rates were calculated according to both RECIST (4%) and WHO (24%) criteria. No MRI parameter in either the diagnostic or response scans had prognostic significance. We recommend that currently primary endpoints for DIPG clinical trials should be overall or possibly progression free survival and that new advanced functional imaging techniques should be explored as possible surrogate markers for novel therapy activity rather than conventional MRI response criteria.

Diffuse brainstem glioma: prognostic factors

“…1,5 Thus, the impact of MRI findings on treatment decisions for brainstem tumors is very high, but the accuracy of MRI-based diagnosis of diffuse brainstem gliomas has not been fully verified by histopathological findings. 8 Thus, some authors have reported that all diffuse brainstem gliomas located above the medulla behave as high-grade astrocytomas, and histological grade is not a significant factor for the survival of these patients. 1,4,5,18,20 Few studies have been conducted concerning prognosis and prognostic factors in brainstem gliomas.…”

Pediatric Brain Tumors: Current Treatment Strategies and Future Therapeutic Approaches

“…Conventional MRI has been shown to be insufficient in predicting clinical outcome. 142 The limited information currently available on molecular pathways involved in the tumorigenesis of these tumors limits a rational approach to test new agents. To date, new trials are often designed based on knowledge gained from other adult or pediatric high-grade glioma experiences.…”

Bevacizumab Targeting Diffuse Intrinsic Pontine Glioma: Results of 89Zr-Bevacizumab PET Imaging in Brain Tumor Models

“…In the past 40 years, the outcome of patients with DIPG has remained unchanged, with less than 10% of the patients being alive 2 years from diagnosis (1,2). Given the lack of gadolinium uptake on MRI in DIPG tumors (3,4), it is plausible that the blood-brain barrier (BBB) in DIPG often remains intact which might explain the resistance to systemic chemotherapy in these patients.…”