Single blood sample could soon screen for several cancers, study suggests

• Researchers have developed a low cost blood test that analyzes DNA methylation patterns in cell-free DNA to potentially detect multiple cancers and other diseases from a single sample.
• By filtering out background DNA and focusing on informative fragments, the test significantly reduces sequencing needs, with an estimated cost of under $20 per sample.
• In a large study, the test detected about 63% of cancers overall and 55% of early stage cancers at 98% specificity, with higher detection rates in high risk liver cancer patients.
• The test can also identify the likely tissue of origin and distinguish among different liver diseases, suggesting its potential as a broad, noninvasive tool for early detection and disease monitoring.

Cell-free DNA (cfDNA) refers to small, fragmented DNA fragments that circulate freely in bodily fluids, such as blood plasma. There is growing interest in using these DNA fragments for noninvasive cancer diagnostics. In particular, circulating tumor DNA (ctDNA) can help to diagnose and manage cancer.

However, many technical challenges remain for cfDNA diagnostics. Namely, this approach is often expensive in clinical settings, as it requires high-depth, high-sensitivity next-generation sequencing to detect small amounts of ctDNA among the high background of normal cfDNA.

Now, a new blood test developed by researchers at the University of California, Los Angeles (UCLA) could offer a low cost way to detect multiple cancers and other diseases from a single blood draw, according to a recent study.

The test, described in Proceedings of the National Academy of Sciences (PNAS), may provide a more affordable and comprehensive approach to early disease detection.