New findings could transform new treatment for rare brain tumor astroblastoma - Children's National

Researchers from Children's National and international collaborators have completed the largest and most comprehensive study to date of a rare brain tumor known as astroblastoma. The findings, published in Neuro-Oncology, reveal that tumors currently classified as "astroblastoma, MN1-altered" are not a single disease but instead comprise three distinct molecular groups with different biological characteristics and clinical outcomes.

The researchers analyzed tumor samples, molecular profiles and clinical data from 200 patients using advanced techniques including DNA methylation profiling, DNA sequencing and RNA sequencing. The findings provide important new insights into how these rare tumors develop and behave and could help guide future treatment decisions.

The hold-up in the field

Astroblastoma is an ultra-rare brain tumor, making it difficult for researchers to collect enough patient data to answer fundamental questions about diagnosis, prognosis and treatment. At the same time, the use of DNA methylation profiling and other advanced molecular tools to classify brain tumors has only emerged in recent years.

As a result, large-scale studies examining the molecular and clinical characteristics of these tumors have been lacking, leaving physicians with limited evidence to guide treatment decisions.

Moving the field forward

The study found that astroblastomas currently grouped under a single diagnosis actually fall into three distinct molecular and clinical categories, including some tumors that do not contain alterations in the MN1 gene.

Researchers also identified potential biomarkers associated with higher-risk disease, including losses of chromosome regions known as 14q and 16q. These findings provide a framework for developing risk-stratified treatment approaches, allowing clinicians to better tailor therapies based on the biology of an individual patient's tumor.

"By bringing together patients from around the world, this study gives us the evidence needed to refine classification, identify higher-risk patients and design therapies tailored to specific molecular subtypes," said study author Adriana Fonseca, MD, director, Rare Brain Tumor Program at Children's National. "Our goal is to turn these discoveries into real-world treatments that improve outcomes for children with rare brain tumors."

The dataset represents the most comprehensive collection of information ever assembled for this rare tumor type and provides the scientific rationale for future global clinical trials.

The patient benefit

For patients and families facing a rare brain tumor diagnosis, better classification can lead to better care. Identifying high-risk biomarkers and actionable therapeutic targets is a critical step toward developing more effective and less toxic treatment strategies.

The ultimate goal is to ensure that children with recurrent rare brain tumors receive therapies that are matched to the specific molecular features of their disease rather than relying on a one-size-fits-all approach.

What's next?

The work is part of a broader effort led by Children's National to better understand and treat rare pediatric brain tumors. Dr. Fonseca leads the International Rare Brain Tumor Registry, which collects tumor samples, molecular profiles and clinical data from patients around the world.

Researchers are now applying similar approaches to other rare brain tumor types while preparing to launch SUPERNOVA-RBT, a clinical trial designed to provide ultra-rapid molecular profiling and personalized treatment selection for patients with relapsed or recurrent rare brain tumors.

Together, these efforts aim to redefine how ultra-rare brain tumors are diagnosed and treated and move the field closer to truly personalized medicine.

Read the full study, "Molecular and clinical stratification of astroblastomas: Three distinct fusion-defined groups informing risk-adapted treatment strategies," in Neuro-Oncology.

Additional authors from Children's National include Roger J. Packer, MD.

This work was supported by a PhD stipend from the German Cancer Research Center (DKFZ), by the City of Vienna Fund for Innovative Interdisciplinary Cancer Research, the Forschungsgesellschaft für Cerebrale Tumore, the Brain Tumour Charity and the anonymous private investors to the Children's National Brain Tumor Institute.