Researchers develop blood test to detect multiple cancers before symptoms emerge

For generations, cancer has hidden in the body until it announced itself through pain or decline — by which point the window for effective treatment had often narrowed. Researchers have now moved closer to a different kind of medicine: one where a simple blood draw, taken before any symptom appears, might reveal a tumor still small enough to be defeated. The science rests on the body's own habit of shedding DNA and molecular traces into the bloodstream, and on the growing human ability to read those traces as warnings. What remains between this possibility and its widespread reality is the pat