TARGETING DIPG:
THE MOST PUZZLING OF PEDIATRIC BRAIN TUMORS Survival has dramatically improved for numerous pediatric cancers over the last several decades, with a notable and very deadly exception: diffuse intrinsic pontine glioma (DIPG). Now, a community of researchers and clinician-scientists have set the stage for a renewed — and better-armed — assault against this beast of a brain tumor.
written by Katie Brind’Amour, PhD
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n the past half-century of oncology care and research, pediatric cancer patients have benefited from skyrocketing survival rates for many diagnoses, with an overall 5-year survival of 83%. Not so for DIPG, for which nearly all efforts have failed: only 2% of children survive 5 years, and more than half are dead in less than a year. While other cancers benefitted from targeted therapies and advances in tumor resection techniques, DIPG tumors have remained virtually untouchable despite inclusion in more than 250 clinical trials for chemotherapies, targeted therapy, combination therapies and immunotherapies. Although some patients respond briefly to radiation (which may extend life about 3 months), the cancer virtually always returns quickly, and to deadly effect.
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PediatricsNationwide.org | Spring/Summer 2021
The tumor is rare, with only 200-300 cases diagnosed each year in children in the United States. Its location in the brain’s pons — the control center, directing the body’s most basic and essential functions — makes DIPG hard to access for biopsy or drug delivery. The diffuse nature of the tumor also makes it essentially unresectable; tumor cells cannot be removed without taking vital healthy tissue with them. These characteristics have made DIPG both difficult to treat and difficult to learn about. As the advent of molecular profiling and cancer genomics catapulted numerous cancer types into the realm of targeted therapies and increased cure rates, DIPG tissue samples to study were in short supply.
