Liquid Biopsy for Cancer Detection

We’re a long way from curing cancer, but one way to work toward this goal is to diagnose cancer early. It’s key to surviving cancer or to living longer with it. Treating it early means cancer has less chance of growing and spreading. That’s why we need a simple blood test to diagnose cancer.  

Today, many so called “liquid biopsies” are in development including looking for cancer markers in urine, saliva and other bodily liquids.  Right now, cancer diagnosis involves a doctor’s evaluation, labs, imaging, and a biopsy to confirm it. But prostate cancer is one of very few cancers already being diagnosed with a blood draw. The blood is screened for molecules or cells that indicate the presence of cancer somewhere in the body.  Some look for specific cancer “signatures” from a tumor’s circulating DNA. These signatures reveal changes in our tumor cells’ DNA including mutations or epigenetic changes. 

New studies suggest a single blood draw may be able to detect over fifty different cancers. Liquid biopsy will be incredibly important for cancers that are now hard to detect until the late stages when people’s lives are at greater risk.  

Pancreatic cancer accounts for nearly 9 percent of all cancer deaths in the US and there’s no early detection for it yet. But in a study, a blood draw detected the cancer in more than 70 percent of patients and correctly identified those without it. Even though it’s not ready for clinical trials, we hope it’s just a matter of time.