Blood test detects common cancer types 4 years before current screening methods
A novel blood-based assay demonstrated the ability to detect five cancer types up to 4 years earlier than current screening methods, according to study results published in Nature Communications.
The noninvasive PanSeer test (Singlera Genomics), which is based on DNA methylation, detected stomach, esophageal, colorectal, lung and liver cancer in 91% of asymptomatic individuals who were diagnosed with cancer 1 to 4 years later using standard detection methods.
Although the test may not predict which individuals go on to develop cancer, it could identify individuals who have cancerous growths but remain asymptomatic, according to the researchers.
“The ultimate goal would be performing blood tests like this routinely during annual health checkups,” Kun Zhang, PhD, professor and chair of the department of bioengineering at the University of California, San Diego, said in a press release. “But the immediate focus is to test people at higher risk, based on family history, age or other known risk factors.”
The Taizhou Longitudinal Study— a 10-year longitudinal study conducted between 2007 and 2017 in China — included 123,115 healthy individuals aged 25 to 90 years who provided plasma samples for long-term storage and were monitored for cancer by regular checkups with physicians. More than 1.6 million specimens have been gathered and archived.
For the current study, researchers analyzed plasma samples of 605 asymptomatic individuals, of whom 191 were diagnosed with stomach, esophageal, colorectal, lung or liver cancer up to 4 years after plasma collection. Investigators also tested samples of 223 patients with cancer, in addition to 200 primary tumor and normal tissue samples.
With a specificity of 96% (95% CI, 93-98), the test detected cancer accurately in 88% (95% CI, 80-93) of post-diagnosis samples.
Moreover, it detected cancer in 95% (95% CI, 89-98) of asymptomatic individuals who were later diagnosed with cancer, although researchers noted that this result needs to be confirmed in larger studies.
“The PanSeer assay provides a preliminary demonstration of early detection of multiple cancer types 4 years prior to conventional diagnosis in a robust manner, and lays the foundation for a noninvasive blood test for early detection of cancer in a high-risk (or average-risk in the future) population,” the researchers wrote. “[Although] much of current research is focused on developing new therapeutics, studies have shown that early detection has the potential to reduce both treatment cost and mortality rates from cancer by a significant amount.”
The five cancer types included in this study account for 261,530 annual U.S. cancer deaths and 2.1 million annual cancer deaths in China. Early detection could significantly decrease deaths due to these cancer types, the researchers added.
“Recent studies have also identified that early detection of cancer could reduce cancer treatment costs by $26 billion annually,” they wrote. “In the future, to fully establish the clinical utility of PanSeer and fully validate the results of pre-diagnostic detection of cancer, we hope to proceed with a large prospective study of healthy individuals to determine if noninvasive cancer screening can reduce cancer deaths in a cost-effective manner.”