Colon cancer screening can help to detect colorectal cancer or colon cancer or large bowel cancer as it is also known and early detection is critical to possible cure.
There are several methods of colon cancer screening which is recommended for individuals who are more at risk:
- The Digital rectal exam is performed by the insertion of a gloved, lubricated finger by the examiner into the rectum of the patient which helps to detect any abnormalities. This is a useful initial method of colon cancer screening though it is able to only detect some tumors in the rectum’s distal part.
- Endoscopy (Sigmoidoscopy and Colonoscopy): This method of colon cancer screening involves a lighted probe (known as the Sigmoidoscope or the Colonoscope as the procedure may be) into the rectum and the lower colon to check for any abnormalities including benign polyps. When a colonoscopy is done it is also possible to remove the polyps found there or to take samples for a biopsy at the same time that the screening is being carried out. A thorough colon cleanse is required prior to carrying out this colon cancer screening procedure.
- Virtual Colonscopy or (Computerized Tomographic Colonography): Here x-rays are used to obtain images of the colon and rectum which are then collated to detect any abnormalities or polyps. This is not as invasive as actual endoscopy and this therefore quicker and causes less discomfort. It also does not require the patient to be sedated.
- Fecal Occult Blood test (FOBT): This test checks for any traces of blood in the stool that may not be visible to look at and is of two main types: the Guaiac FOBT is the way to chemically detect heme, which is the iron-containing component of hemoglobin inside blood. Then there is the Immunochemical FOBT which uses antibodies for the same purpose; to detect hemoglobin in the stool.
- Double contrast barium enema (DCBE): In this method of colon cancer screening, an enema with a barium sulphate solution is administered. The barium coats the inside of the colon, and then the colon is inflated. In this distended state, x-rays are taken to detect precancerous polyps or existing cancer. This method though is not effective in detecting flat or very small polyps.
Those individuals with only an average risk of developing this kind of cancer should start to use colon cancer screening options at age 50 after speaking to the doctor about which method is most appropriate.
This frequency could be determined by several factors such as a personal history or a family history of colorectal cancer or adenomatous polyps or a family history of these conditions.
Another factor is a personal history of Crohns disease or ulcerative colitis (chronic inflammatory bowel disease). According to one’s personal risk factors, the frequency of testing and the kind of testing (less or more invasive) is decided.