Cancers. >> we're losing almost 2,000 of our loved ones every day and it is because we're finding those cancers too late. >> reporter: galleri looks at blood for dna shed by cancer tumors. if it sees that dna, then it predicts where the cancer is. >> if it says cancer signal detected. predicted location ovary, the doctor will know to do an imaging test of the pelvis. >> reporter: the galleri test is available now by prescription but is not covered by insurance. cost to the patient $950 a positive result is not always right up to half will turn out not to be cancer but researchers at the nation...