University of Cincinnati researchers are starting a clinical trial to determine if they can detect brain cancer in spinal fluid. This kind of a test, called a "liquid biopsy," appears to be more accurate than MRIs which sometimes prompt unnecessary surgery.
UC neurosurgeon Dr. Matthew Garrett says glioblastoma, an aggressive form of brain cancer, always grows back. So instead of subjecting patients to repeated surgeries to confirm additional growths, he wondered if just checking spinal fluid would work. A clinical trial will validate this theory.
"So to join this trial initially, before the first surgery, you consent to have a small part of your brain fluid that's discarded during surgery, we save it and then we normally look for tumor DNA in that fluid," he says.
After the surgery, chemotherapy and radiation, the patient would get their spinal fluid checked. At this point it shouldn't show any tumor DNA because the cancer has been removed, says Garrett.
"With your first surgery I leave a little tube in a bag that we can sample from every few weeks and that we will be able to detect far, far earlier when this tumor is growing back and it will not lie to us," he says.
He plans to follow 10-15 patients over the course of their cancer battles.
Could Liquid Biopsies Be Used To Detect Other Cancers?
Dr. Trish Wise-Draper is an oncologist who runs UC's clinical trials. She says this concept can be applied to other tumors.
"One of the things that is really difficult for us is repeat biopsies or repeat surgeries," she says. "They are really hard on patients. So if we can take a simple blood test - or in this case, fluid from the CSF - and be able to know if the tumor is back or not and if we need to change our treatment strategy to do something more aggressive, would be ideal."
Wise-Draper says immunotherapy can sometimes cloud whether the treatment is working, so this would be another reason to use liquid biopsies.