Colorectal cancer: Towards a new test

The National Cancer Institute (INCA) launched Tuesday, March 18, the second national week against colorectal cancer. From 24 to 30 March, it will educate physicians and patients at screening of a disease that affects 37,000 people each year, the third most common cancer. Announced in late 2007, the widespread screening for colorectal cancer is expected to be completed in late 2008. In addition, the test currently used should be replaced by a more efficient immunological test. Already established in 88 departments, the colorectal cancer screening is offered to some 16 million men and women aged 50 to 74 years, but is not always accepted. "Currently, the test reference is the Hemoccult II," says Dr. Jerome Viguier, Head of screening INCa. With this test microsaignements not visible to the naked eye in the stool that widespread screening occurs. But in March 2007, the National Academy of Medicine has put into question the "poor performance" of the test Hemoccult II. Bleeding occult justify conducting a colonoscopy. Practiced under anesthesia, the examination of the colon and rectum using a fiber optics can detect a lesion type of adenoma (polyp). On adenomas miles, one hundred reaching 1 cm in diameter and 25 become cancerous. ANOTHER METHOD Dr. Guy Launois (CHU de Caen) conducted a study on another type of test, based on an automated immunoassay method, the dose amount of haemoglobin present in the stool sample. "Results on 20000 people, 30000 and soon showed the superiority of the test on the Hemoccult II, primarily for large adenomas," notes Dr. Viguier. The INCa funded further studies on the immunological test and the respective performances of the various existing tests. "There is a particular determine the level of sensitivity that should have immunological consideration. With a threshold too restrictive, it miss cancers, it is too broad, it would result in too many unnecessary colonoscopies," says Dr. Viguier. The INCA will launch a tender to select the immunological test, which will take over from the Hemoccult II.