Colorectal cancer, or cancer of the colon and rectum, continues to be the second-leading cause of cancer deaths in the United States.
It is estimated that almost 140,000 new cases will be diagnosed in the U.S. in 2014, and more than 50,000 people will die from the disease.
The incidence is slightly higher in men than women, and increases dramatically after age 50, with 90 percent of new colorectal cancer cases found in that age group. Additional risk factors include but are not limited to personal or family history of colon cancer or colon polyps, certain inflammatory bowel diseases, and some hereditary conditions such as familial adenomatous polyposis and hereditary non-polyposis colon cancer. Check with your medical provider for additional guidelines and risk factors.
Colon cancer rates have decreased significantly in some parts of the country over the past 10 years, largely attributed to increased rates of early screening for the disease. The best opportunity for decreasing death rates from this cancer is to prevent it through early screening and detection.
In the vast majority of cases, colorectal cancer begins as polyps, which are small growths that develop in approximately 25 percent to 30 percent of people after age 50. These polyps generally do not cause symptoms, but may, over a period of time, grow and turn into cancer. If the polyps are removed when they are small, the cancer may be prevented.
Since polyps do not cause symptoms, they can only be found with screening tests. The test that has consistently been shown to be the best exam for the detection and removal of polyps is colonoscopy. Various studies have shown that the use of this test can decrease colorectal cancer rates by 60 percent to 85 percent.
A colonoscopy involves the visual examination of the inside of the colon with a colonoscope, and permits removal of most polyps at the time of the procedure. This exam is usually done with sedation and requires a day of preparation and a day off work, although the exam itself usually only takes about 30 minutes.
Other screening tests for colorectal cancer are available, although less effective in prevention than a colonoscopy.
Fecal occult blood tests involve testing a stool sample for the presence of blood. However, as only a small number of colon polyps cause bleeding, and not all bleeding is due to polyps, the test is not very accurate. Flexible sigmoidoscopy is similar to colonoscopy in that it uses a flexible scope to evaluate part of the colon, but it only examines the lower third of the large intestine, and may miss any lesions in the other two-thirds of the colon. Virtual CT colonography is an X-ray test used to evaluate the colon, but does not permit any therapeutic intervention (such as polyp removal) and requires a bowel purge similar to that of a regular colonoscopy. If polyps are seen on this exam, a regular colonoscopy is required to remove them.
Current recommendations are that screening should begin at age 50 and continue at recommended intervals, depending on what screening exam is done. However, it is important to note that if an individual has an increased risk for developing colorectal cancer screening should begin at an earlier age and be done at more frequent intervals. Your medical provider can make specific recommendations based on your history and risk factors.
What are the symptoms of colorectal cancer? Oftentimes, none at all. It can, however, present with bleeding, pain and cramping in the lower abdomen, changes in bowel habits, anemia and/or unexplained weight loss. These symptoms could have other causes, but always check with your doctor.
Some studies have shown a healthy lifestyle, including eating a diet high in fiber and low in saturated fats, plus regular exercise and avoidance of tobacco products can also help reduce your risk of colorectal cancer.