Every year between March and April we turn the spotlight on colon, or colorectal cancer, in our campaign for early detection. Fortunately, efforts at spreading the word about the disease have worked. Through screenings, polyps are being found before they can develop into cancers and cancers are being found earlier, when they are easier to cure. As a result, the death rate from colorectal cancer has been dropping for the past 15 years. Today, there are around one million colon cancer survivors in the United States.

The struggle is far from over, though. Nearly 60,000 Americans will die this year from colorectal cancer, making it the nation's second leading cause of cancer-related deaths. That number could be cut in half, experts believe, if everyone over age 50 were tested for the disease. The first step on the path to achieving that goal is to educate the public about the various factors that influence our risk for colorectal cancer.

Risk Factors for Colorectal Cancer

No one knows the exact cause of most colorectal cancers, but researchers have identified the following risk factors that increase a person's chance of developing either precancerous polyps or colorectal cancer:

Age: Adults can develop colorectal cancer at any age, but more than 90 percent of people diagnosed with it are older than 50.

A personal history of colorectal cancer: Someone who has had colorectal cancer, even though it has been completely removed, is more likely to develop new cancers in other areas of the colon and rectum. The chance of this happening is greater if the first colorectal cancer occurred at age 60 or younger.

A personal history of colorectal polyps: Someone who has had an adenomatous-type polyp is at increased risk of developing colorectal cancer. This is especially true if the polyps are large or if there are many of them.

A personal history of chronic inflammatory bowel disease (IBD): This includes ulcerative colitis and Crohn’s disease. Someone with IBD is at increased risk of developing colorectal cancer. Note: IBD is not the same condition as IBS, or irritable bowel syndrome. IBS does not carry an increased risk for colorectal cancer.

A family history of colorectal cancer: While most colorectal cancers occur in people without a family history of colorectal cancer, about 40 percent of colorectal cancer (or adenomatous polyps) is hereditary in nature. Someone is considered at increased risk for these conditions if at least one first-degree relative had them before age 60 or if two or more first-degree relatives had them at any age. (First-degree relatives are defined as parents, siblings and children.)

Ethnic background: Jews of Eastern European descent (Ashkenazi Jews) have a higher rate of colorectal cancer. Recent research identified a genetic mutation leading to colorectal cancer in this group.

Racial background: African Americans have the highest incidence and mortality rates of colorectal cancer in the United States. The reason for this is uncertain.

A diet mostly from animal sources: A diet that is high in fat, especially fat from animal sources, can increase the risk of colorectal cancer. Over time, eating a lot of red meat and processed meat can increase colorectal cancer risk.

Physical inactivity: People who have a sedentary lifestyle have a greater chance of developing colorectal cancer.

Obesity: People who are overweight have a higher risk of developing and dying from colorectal cancer.

Diabetes: People with diabetes have a 30 to 40 percent increased chance of developing colorectal cancer. They also tend to have a higher death rate after diagnosis.

Smoking: Recent studies indicate that smokers are 30 to 40 percent more likely than non smokers to die from colorectal cancer. That’s because some of the cancer-causing substances in smoke are swallowed and can cause digestive system cancers, such as colorectal cancer.

Alcohol consumption: Heavy alcohol consumption has been linked to colorectal cancer. While some of this may be due to the effects of alcohol on folic acid in the body, it still would be wise to avoid heavy alcohol use.

Colorectal Cancer Screening

Some of the risk factors for colorectal cancer can be avoided or lessened. Others cannot. Regardless, people with any of the above risk factors need to be extra vigilant about getting regular colorectal cancer screenings, as well as tests for cancerous and precancerous polyps.

Screening allows for the early detection of colorectal cancer when it is highly curable, as well as the detection and removal of growths, or polyps, that could become cancer. This prevents the development of cancer altogether. A number of different types of tests are used to screen for colorectal cancer. A doctor will help the patient determine which ones are appropriate for him or her based on age and the presence of risk factors.

American Cancer Society Guidelines on Screening and Surveillance for the Early Detection of Colorectal Adenomas and Cancer – Women and Men at Increased Risk or at High Risk

¹ If colonoscopy is unavailable, not feasible, or not desired by the patient, double-contrast barium enema (DCBE) alone, or the combination of flexible sigmoidoscopy and DCBE are acceptable alternatives. Adding flexible sigmoidoscopy to DCBE may provide a more comprehensive diagnostic evaluation than DCBE alone in finding significant lesions. A supplementary DCBE may be needed if a colonoscopic exam fails to reach the cecum, and a supplementary colonoscopy may be needed if a DCBE identifies a possible lesion, or does not adequately visualize the entire colon and rectum.

Remind Family and Friends About Colorectal Cancer Screening

If you know someone who is 50 or older, or who has other risks for colorectal cancer, one of the most helpful things you can do is remind them to be tested.

One way to do this is to sign them up to receive our free, customized colon test reminder – or send them an e-card with a compelling message about cancer screening.

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