Patients may experience abdominal pain or tenderness, a change in bowel habits, rectal bleeding, or blood in the stool. Anemia and weight loss may also occur. Because these symptoms are also signs of other conditions, a thorough examination is required to determine the exact cause of the problem.
Age is an important risk factor for the development of colorectal cancer.
The disease is most common after age 40. Researchers estimate that the risk of colorectal cancer for a previously healthy person doubles with each decade of life from age 40 through age 80. Personal or family history of colorectal cancer or polyps is also associated with a higher risk for the development of the cancer. Unfortunately, only about 37 percent of colorectal cancers are detected in this early stage. By the time the cancer has spread to nearby organs or lymph nodes, 5-year survival rates drop to 63 percent.