This new blood test could spot cancer up to 3 years before symptoms

A Johns Hopkins University study shows that a simple blood test may detect cancer long before symptoms emerge, potentially transforming early treatment and survival rates

A simple blood test developed by researchers at Johns Hopkins University could detect cancer up to three years before symptoms appear. By identifying tiny fragments of tumour DNA circulating in the bloodstream long before the disease becomes evident, the test holds promise for early intervention and significantly better outcomes.

 

According to a statement on the university’s website, a new study published in Cancer Discovery demonstrated that the multicancer early detection (MCED) blood test could identify tumour-derived genetic material in blood samples well before any clinical signs were visible. The team used archived blood samples from the Atherosclerosis Risk in Communities (ARIC) study—originally focused on heart disease—which provided valuable data for cancer detection analysis.

How does the early cancer detection test work?

The MCED blood test detects circulating tumour DNA (ctDNA)—tiny fragments of genetic material shed by tumours into the bloodstream. These fragments can signal the presence of cancer even before any symptoms develop. The test uses highly sensitive sequencing technologies to pick up these subtle changes earlier than traditional screening methods.

 

Researchers analysed plasma samples from 52 individuals: 26 who were later diagnosed with cancer within six months of blood collection, and 26 who remained cancer-free. Of these, eight tested positive for tumour DNA at the time of sampling—and all eight were diagnosed with cancer within four months.

Can it really detect cancer years in advance?

For six of the eight positive cases, researchers also examined earlier blood samples taken 3.1 to 3.5 years prior. In four of these cases, tumour-related mutations were already detectable—suggesting the test could potentially detect cancer over three years before diagnosis.

Why does early detection matter so much?

“Three years earlier provides time for intervention. The tumours are likely to be much less advanced and more likely to be curable,” said lead author Dr Yuxuan Wang of Johns Hopkins.

 

Early detection significantly increases the chance of successful treatment and long-term survival, possibly changing the landscape of cancer care. Senior author Dr Nickolas Papadopoulos noted that while the results are promising, more research is needed to determine appropriate follow-up protocols after a positive test, to avoid unnecessary anxiety or treatment.

Is the test available to the public yet?

Not yet. The MCED blood test is still undergoing research and is not currently available for general screening. The researchers emphasised the need for larger-scale studies before the test can be used in routine clinical practice.

 

Still, the findings offer hope for a future where cancer can be detected and treated far earlier than current diagnostic tools allow.  For more health updates, follow #HealthWithBS 

This content is for informational purposes only and is not a substitute for professional medical advice.