United Press International

　　Wednesday, December 22, 2004

　　INDIANAPOLIS, Dec 22, 2004 (United Press International via COMTEX) —— Indiana researchers say a non-invasive colorectal cancer test that checks for DNA mutations in stool samples showed good sensitivity and specificity.

　　The Indiana University School of Medicine study, to be summarized in Thursday's issue of the New England Journal of Medicine, did not have the detection rate of a colonoscopy.

　　In average risk, asymptomatic individuals the established test for blood hidden in stool found only 13 percent of colorectal cancer, while the new stool DNA test detected 52 percent of the cancers. Colonoscopy, which is presumed to find all colon cancers, remains the "gold standard" against which all other tests are measured.

　　Typically, colorectal cancer develops slowly over a period of several years, usually beginning as a growth of tissue known as a polyp that develops on the lining of the colon or rectum. Most cancerous lesions bleed intermittently, however many precancerous polyps do not bleed. Absence of fecal occult blood cannot rule out cancer or precancerous lesions.