Blood test can predict prognosis in deadly brain cancer

A blood test that measures the amount of cell-free DNA (cfDNA) in the bloodstream—called a liquid biopsy—correlates with how patients will progress after they are diagnosed with glioblastoma (GBM), the deadliest and most common primary brain tumor in adults

MRI scan of brain and hand with a red marker pointing at a mark on the scan.


In a new study, researchers from the Abramson Cancer Center are the first to show that patients with a higher concentration of cfDNA—circulating DNA that cancer and other cells shed into the blood—have a shorter progression-free survival than patients with less cfDNA, and that cfDNA spikes in patients either at the time of or just before their disease progresses. The team also compared genetic sequencing of solid tissue biopsies in GBM side-by-side with the liquid biopsies and found that while both biopsies detected genetic mutations in more than half of patients, none of those mutations overlapped, meaning liquid biopsy may provide complementary information about the molecular or genetic makeup of each tumor. Clinical Cancer Research, a journal of the American Association for Cancer Research, published the findings.

“Doctors have begun using liquid biopsies more frequently to monitor certain cancers—particularly lung cancer—in recent years as research has shown their effectiveness in other disease sites. But until now, there has been little focus on the clinical utility of liquid biopsy in brain tumors,” said the study’s senior author Erica L. Carpenter, director of the Liquid Biopsy Laboratory and a research assistant professor of medicine.

The findings may eventually prove impactful for GBM patients. The disease is particularly aggressive, and while most estimates show there are around 11,000 new cases each year, the five-year survival rate is between 5 and 10 percent.

Read more at Penn Medicine News.