The U.S. Food and Drug Administration announces the approval of Cologuard, the first non-invasive DNA screening test for colorectal cancer. The screening test is stool-based and detects red blood cells and DNA mutations that could suggest specific types of abnormal growths that could be cancerous, such as colon cancer, or a precursor to cancer.

Cologuard works by detecting hemoglobin in a stool sample. Hemoglobin is a protein molecule that is a part of blood. The screening test can also find mutations that are linked with colon cancer in the DNA of cells. Patients with positive test results will be urged to undergo a diagnostic colonoscopy.

Alberto Gutierrez, PhD, director of the Office of In Vitro Diagnostics and Radiological Health at the FDA’s Center for Devices and Radiological Health, said in a statement, “This approval offers patients and physicians another option to screen for colorectal cancer.” He continued, “Fecal blood testing is a well-established screening tool and the clinical data showed that the test detected more cancers than a commonly used fecal occult test.”

The safety and effectiveness of the screening test was established in its clinical trial, which involved 10,023 subjects. Cologuard effectively detected cancers and advanced adenomas more frequently than the fecal immunochemical test, a frequently used non-invasive screening test that detects blood in the stool.

According to cancer.org, colorectal cancer starts in the colon or rectum and often begins as a noncancerous polyp on the  inner lining of the colon or rectum.