A new blood test can identify many types of cancer and can even detect some malignancies—and pinpoint their location—at early stages, when they’re easier to treat.
The liquid biopsy test, from the biotechnology company GRAIL, analyzes DNA from cancer cells circulating in the blood. A study of more than 2,000 people found that the test’s sensitivity, or its ability to accurately identify cancer when present, was 76% for 12 deadly cancer types, including lung cancer, colorectal cancer, ovarian cancer and pancreatic cancer. The accuracy was 34% for Stage I cancer, 77% for Stage II, 84% for Stage III and 92% for Stage IV, or metastatic disease.
The test’s specificity, or its ability to correctly rule out cancer when not present, was 99%.