(Washington Post) – For years, it has been one of the most tantalizing ideas in medicine: One day, a simple blood test will detect nascent cancers — allowing doctors to intervene when tumors may be easier to treat.

A study published this month in Cancer Discovery found that three years before a handful of cancer patients were diagnosed, some promising tests could detect trace amounts of cancer genetic material floating in their blood, shed by tumors the people didn’t yet know existed. (Read More)