Colon Carcinoma at 10x Magnification
Routine screening for colon cancer is often recommended for individuals 50 years of age or older. This procedure generally consists of a fecal occult blood test, which can reveal the presence of blood in fecal material even when it cannot be detected by the eye, and flexible sigmoidoscopy, which involves the use of a tube-like instrument to inspect the rectum and lower colon. Individuals known to be at high risk for the disease may also be advised to periodically undergo the more extensive examination known as a colonoscopy, in which the condition of the entire colon can be assessed. Diagnosis of colon cancer often initially involves the same techniques utilized for screening purposes, but a biopsy is needed to confirm the presence of cancer cells. A number of imaging techniques, including x-rays, magnetic resonance imaging (MRI) and computed tomography (CT) scans, are commonly used during the staging of the cancer.