Funded by the Dick Vitale Pediatric Cancer Research Fund
Primary brain tumors are the most common solid tumors in children. They are also the most frequent cause of cancer-related death in children and teens. Genetic profiling is an important tool in the treatment of these tumors. DNA sequencing provides information for proper diagnosis. It can also be used to understand how tumors change over time and to monitor response to treatment. However, performing biopsies is very challenging for brain tumors. Many tumors are in important areas of the brain and can’t be fully removed or repeatedly sampled.
“Liquid biopsy” is a new tool that can be used to diagnose cancer and track response for some systemic tumors. It works by detecting small pieces of DNA that break off from tumors. These can be found in the cerebrospinal fluid (CSF) and in blood (circulating tumor DNA, ctDNA). Accessing these “liquids” is usually easier and has fewer complications than surgery.
We previously showed that CSF ctDNA can be used to diagnose brain tumors and that ctDNA is associated with active disease. But there are instances where CSF ctDNA is not informative due to technical limitations. We propose to improve how these samples are analyzed so CSF liquid biopsies can help more patients. Our prior work was retrospective. For this project, CSF ctDNA monitoring will be added to a clinical trial. We will investigate whether there is a relationship between CSF ctDNA and disease burden. Validating CSF liquid biopsy could greatly improve how pediatric primary brain tumors are diagnosed and treated.