Colorectal Cancer

Your risk of getting colorectal cancer increases as you get older. More than 90% of cases occur in people who are 50 years old or older. Other risk factors include having—

• Inflammatory bowel disease such as Crohn’s disease or ulcerative colitis.
• A personal or family history of colorectal cancer or colorectal polyps.
• A genetic syndrome such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colorectal cancer (Lynch syndrome).

Lifestyle factors that may contribute to an increased risk of colorectal cancer include—

• Lack of regular physical activity.
• A diet low in fruit and vegetables.
• A low-fiber and high-fat diet.
• Overweight and obesity.
• Alcohol consumption.
• Tobacco use.

Colorectal polyps and colorectal cancer don’t always cause symptoms, especially at first. Someone could have polyps or colorectal cancer and not know it. That is why getting screened regularly for colorectal cancer is so important.

If you have symptoms, they may include—

• Blood in or on your stool (bowel movement).
• Stomach pain, aches, or cramps that don’t go away.
• Losing weight and you don’t know why.

If you have any of these symptoms, talk to your doctor. They may be caused by something other than cancer. The only way to know what is causing them is to see your doctor.

Almost all colorectal cancers begin as precancerous polyps (abnormal growths) in the colon or rectum. Such polyps can be present in the colon for years before invasive cancer develops. They may not cause any symptoms. Colorectal cancer screening can find precancerous polyps so they can be removed before they turn into cancer. In this way, colorectal cancer is prevented. Screening can also find colorectal cancer early, when there is a greater chance that treatment will be most effective and lead to a cure.

Research is underway to find out if changes to your diet can reduce your colorectal cancer risk. Medical experts don’t agree on the role of diet in preventing colorectal cancer, but often recommend a diet low in animal fats and high in fruits, vegetables, and whole grains to reduce the risk of other chronic diseases, such as coronary artery disease and diabetes. This diet also may reduce the risk of colorectal cancer. Also, researchers are examining the role of certain medicines and supplements in preventing colorectal cancer.