New DNA test detects cancer early

A universal cancer test that can detect tumours 10 years before they become dangerous is being developed.

Researchers told the world's largest oncology conference in Chicago, US, that they had successfully tested the blood of 120 patients with breast, lung or prostate cancers.

"Liquid biopsies" are risk-free and repeatable procedures that work by detecting DNA fragments of tumours in the blood. These would particularly benefit patients with cancers that have poor survival rates because they are often detected at a late stage, such as lung, pancreatic and ovarian. They also promise to detect the size and location of tumours.

A universal screening test could reduce cancer mortality by 90% and experts predict that rudimentary tests will soon be available for as little as R2,500.

Doctors currently rely on scans and biopsies to detect cancer which are usually only carried out when a patient feels unwell and some procedures come with the risks of surgery.

The trial was funded in part by Bill Gates and Amazon founder Jeff Bezos.