A reliable, at-home colon cancer screening test that identifies DNA mutations in stool samples could soon supplement the dreaded colonoscopy. Exact Sciences Corp.'s noninvasive tool is far more predictive of colon cancer than the standard stool blood test because it screens for mutations associated with the presence of tumors. In a study of more than 1,000 patients, the test detected 85 percent of colon cancers, 64 percent of precancerous polyps, and 90 percent of healthy samples, researchers said Thursday at an American Association for Cancer Research conference. About 150,000 people are diagnosed with colon cancer each year, and 50,000 die from the disease annually. Often, that's because people shy away from invasive and somewhat risky colonoscopies until they have symptoms—indicating that the disease may already be advanced, The Wall Street Journal reports. "The noninvasive test we have developed is simple for patients, involves no diet or medication restriction, no unpleasant bowel preparation, and no lost work time, as it can be done from home," David Ahlquist, a Mayo Clinic researcher who helped develop the test, said at the conference. "Positive tests would be followed up with colonoscopy." The tool requires at least another year of development before it's ready for clinical use, researchers said.