A blood test may help doctors detect the most common form of pancreatic cancer in its early stages, according to a new study.
The test could also accurately stage a patient’s disease and guide doctors to an appropriate treatment.
Researchers say the test—known as a liquid biopsy—had more accurate results detecting disease in a blind study than any other known biomarker alone, and was also more accurate at staging disease than imaging alone.
Pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer, is the third leading cause of cancer deaths. The overall five-year survival rate is just 9%, and most patients live less than one year following their diagnosis.
Catching the disease before it has progressed or spread poses one of the disease’s biggest challenges. If the disease is caught early, patients may qualify for surgery to remove the cancer, which can be curative.
For locally advanced patients—meaning patients whose cancer has not spread beyond the pancreas but who are not candidates for surgery based on the size or location of the tumor—treatment involves three months of systemic therapy like chemotherapy or radiation, then reassessing to see if surgery is an option.
For patients whose disease has spread, there are currently no curative treatment options.
“Right now, the majority of patients who are diagnosed already have metastatic disease, so there is a critical need for a test that can not only detect the disease earlier but also accurately tell us who might be at a point where we can direct them to a potentially curative treatment,” says Erica L. Carpenter, a research assistant professor of medicine and director of the Liquid Biopsy Laboratory at Penn and co-senior author of the study in Clinical Cancer Research.
Researchers developed a blood test to screen for a panel of biomarkers instead of just one biomarker on its own. These markers include carbohydrate antigen 19-9 (CA19-9) and KRAS mutational burden, which are known to be associated with PDAC.
In a blinded test group of 47 patients (20 with PDAC, 27 who were cancer free), the test was 92% accurate in detecting disease, which outperforms the best known biomarker, CA19-9 (89%), alone.
The researchers then used samples from the 25 patients who imaging showed did not have metastatic disease. The Penn test was 84% accurate in determining disease staging, significantly higher than imaging alone (64%).
While the test still needs validation in a larger cohort, researchers say they are excited by the promise of what it could potentially mean for a patient population in need of this kind of advancement.
“If validated, this test could not only provide a key tool for at-risk patients, but also a monitoring tool for patients with certain known risk factors like BRCA mutations,” Carpenter says.
The Pennsylvania Department of Health, the National Institutes of Health, the American Cancer Society, and Congressionally Directed Medical Research Programs supported the work.