Blood Tests Offer Hope for Earlier Cancer Detection, But Challenges Remain
A routine blood test saved John Gormly’s life. Four years ago, the 77-year-old CEO of a construction company near Newport Beach, California, received a diagnosis of Stage 2 colon cancer after a blood test flagged a potential issue, a discovery confirmed by a subsequent colonoscopy. His story underscores a rapidly evolving landscape in cancer detection: the rise of “liquid biopsies” – blood tests designed to identify cancer signals with unprecedented ease.
The test gormly took was Shield, a newly approved diagnostic tool from Guardant Health. After surgery to remove the tumor, gormly was back to work within 10 days, a testament to the power of early detection. Shield’s FDA approval in July 2024, and subsequent coverage by Medicare, marks a significant step forward in making this technology accessible. Though, it’s just one piece of a larger puzzle, as scientists develop blood tests for a growing number of cancers – including breast, pancreas, and stomach – and even tests capable of detecting multiple cancers simultaneously.
The Promise of Liquid Biopsies
Liquid biopsies offer a less invasive alternative to conventional screening methods like colonoscopies and biopsies. They work by detecting minute fragments of DNA released into the bloodstream by cancer cells or precancerous growths. Some tests also analyse chemical tags on DNA, known as methyl groups, to differentiate between cancerous and normal cells.
“That’s why there’s an possibility for blood tests that is really powerful because people are inclined to do blood tests; they’re co
