Colorectal Cancer Risk Assessment
Cancers of the colon or rectum (colorectal cancer) usually develop slowly, over many years. Excluding skin cancers, colorectal cancer is the third most common cancer in both men and women in the U.S. and the second most common cause of cancer-related deaths overall, according to the American Cancer Society (ACS). Still, the death rate from colorectal cancer has been dropping for more than 30 years because of better detection and treatment. Take this simple assessment to learn about your risks for colorectal cancer.
Processed meat intake, even in small amounts, and red meat in moderate to high amounts, increases risk.
Your results
Your relative risk for developing colorectal cancer is . Your risk level is determined by the highest-level risk factor you have reported. (A risk factor is anything that increases your chance of getting a disease or a condition.) Your risk factors and their relative significance are listed below.
The information you provided suggests that your relative risk for developing colorectal cancer is low. You have none of the common risk factors covered in this assessment. Your results show the following preventive factors that help decrease your likelihood developing colorectal cancer by varying degrees:
Significant risk factors:
- You have a personal history of colorectal adenomatous polyps. (Other types of polyps, such as hyperplastic polyps, do not increase risk.)
- You have a family history of colorectal cancer.
- You have a family history of familial adenomatous polyposis (FAP).
- You have a family history of hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome.
- You have a family history of Gardner Syndrome.
- None
Moderate risk factors:
- You are years old. Risk increases rapidly starting at age 50.
- You are obese; your BMI is 30 or greater.
- You smoke.
- You consume more than 2 alcoholic drinks a day (if a man) or more than 1 alcohol drink a day (if a woman).
- You have had ulcerative colitis for 8 years or more.
- You have had Crohn's disease for 8 years or more.
- None
Mild risk factors:
- You do not get enough exercise.
- You are overweight (but not obese).
- You eat processed or red meat.
- You are a former smoker.
- None
Your results also show the following preventive factors that decrease your risk for colorectal cancer by varying degrees:
- You are not yet 50 years old.
- You get at least 30 minutes of moderate exercise on most days.
- You have stayed at a healthy weight; your BMI is less than 25.
- You don't eat processed or red meat.
- You are a vegetarian.
- You have never smoked cigarettes.
- You have had a fecal occult blood test within the last year.
- You have had a sigmoidoscopy within the last 5 years.
- You have had a colonoscopy within the last 10 years.
Understanding risk factors for colorectal cancer
Important risk factors for colorectal cancer include family and personal health history, especially:
- Family history of colorectal cancer or hereditary colorectal cancer syndromes.
- Personal history of adenomatous polyps or chronic inflammatory bowel disease. Adenomatous polyps of the colon or rectum are noncancerous growths that may develop into cancer if not treated. Chronic inflammatory bowel disease includes ulcerative colitis and Crohn disease.
Other factors that increase the risk for colorectal cancer, according to the ACS:
- Being of African-American or Eastern European Jewish descent
- Advancing age. Most people with colorectal cancer are 50 or older.
- Lifestyle choices, particularly, a diet high in red meat and processed meat, lack of exercise, and smoking
- Excess alcohol consumption (more than 2 drinks a day for men or 1 drink a day for women).
- Being overweight or obese
- Having type 2 diabetes
The importance of screening
Screening is important for preventing colorectal cancer. Screening can find polyps, which are growths that can become cancer. These polyps can be removed before they turn into cancer, the ACS says. Screening can also find cancer early, when it is small, hasn't spread and is easier to treat.
People who have no other risk factors except advancing age should begin regular screening for colorectal cancer at age 45, according to the ACS and U.S. Preventive Services Task Force (USPSTF). If you have a family history or other risk factors for colorectal cancer, talk with your healthcare provider about the need for screening at an earlier age or for more frequent screening. Several screening tests are available, but medical experts differ on which test is better or how often to get screened.
For those who are 45 years old with average risk for colorectal cancer, the ACS and USPSTF recommend:
- A highly-sensitive guaiac fecal occult blood test (gFOBT) or fecal immunochemical test (FIT) every year, or
- A flexible sigmoidoscopy every 5 years (or every 10 years with yearly FIT stool test), or
- A colonoscopy every 10 years, or
- A CT colonography (virtual colonoscopy) every 5 years, or
- A stool DNA test every 1 to 3 years
You'll need a follow-up colonoscopy if you choose any test other than a colonoscopy and have an abnormal result.
The ACS recommends that you start testing at an earlier age or have more frequent screening if you have any of these risk factors:
- A family history of colorectal cancer or polyps. If your parent, sibling or child was diagnosed at a younger age than usual, or you have 2 immediate family members diagnosed at any age.
- A family history of hereditary colorectal cancer syndromes, such as familial adenomatous polyposis (FAP) or hereditary nonpolyposis colon cancer (HNPCC or Lynch syndrome).
- A personal history of colorectal cancer or adenomatous polyps.
- A personal history of chronic inflammatory bowel disease.
Description of screening tests
Visual tests:
Flexible sigmoidoscopy. A slender, flexible, hollow, lighted tube with a small video camera on the end is put through the rectum into the lower part of the colon to look for polyps and cancers. Any small polyp found may be removed; polyps, even those that aren't cancer, may turn into cancer over time. You are awake. No medicines are used for this test. This test is used less commonly in the U.S. You will do bowel preparation before the test to clear stool from your colon and rectum.
Colonoscopy. Just as in the sigmoidoscopy, a slender, flexible, hollow, lighted tube is put through the rectum into the colon to look for polyps and cancers. But a colonoscope is longer and allows the healthcare provider to see the entire length of the colon. If a small polyp is found, your provider may remove it. Polyps, even those that are not cancer, eventually may turn into cancer over time. You will do bowel preparation before the test to clear stool from your colon and rectum. You will be given anesthesia to make you sleep during this test. You'll need someone to drive you home afterward. Some people might prefer one of the other screening tests, but if you choose any of the other tests and an abnormality is found, you will likely still need a colonoscopy.
CT colonography (virtual colonoscopy). This test uses CT scans to check the colon for polyps or masses. A computer uses the images to make a 3-D model of the colon. You are awake for this test. For virtual colonoscopy, nothing is put into the colon, but a small tube must be put into the rectum to pump air into the colon. The bowel preparation is the same as for a colonscopy.
Stool tests:
Fecal occult blood test (FOBT). This test can find hidden blood in the stool. Small samples of stool are smeared on a card, and a chemical is added to look for a color change that means blood is present. Blood in the stool can be a sign of polyps or cancers.
Fecal immunochemical test (FIT). This test is a lot like a fecal occult blood test, but there are no diet or medication restrictions before the test.
Stool DNA test. This test looks for blood and certain DNA changes that cancer or polyp cells can shed into stool. For this test, an entire stool sample is collected and sent to a lab for testing.
Treatment for colon polyps and colorectal cancer
If your health care provider finds a precancerous polyp, it can be removed during a colonoscopy. If your provider finds cancer, they will discuss treatment options with you. The main types of treatment for colorectal cancer are surgery, radiation therapy, chemotherapy, and targeted therapy. Depending on how advanced the cancer is (how much there is and where it is), treatments may be combined or used one after another.
Reducing your risk for colorectal cancer
You can reduce your risk for colorectal cancer! Here's what the ACS recommends:
- Get to and stay at a healthy weight. Ask your healthcare provider what a healthy weight is for you. They can help you reach your goal weight.
- Eat a healthy diet that includes plenty of fruits, vegetables, and whole grains. Limit how much red and processed meat you eat.
- If you smoke, quit.
- Limit how much alcohol you drink. It's best not to drink.
- Get regular exercise. Aim for at least 75 minutes of vigorous activity or 150 minutes of moderate physical activity a week.
This information is not intended as a substitute for professional health care. Always consult with a health care provider for advice concerning your health. Only your health care provider can do a thorough disease risk assessment or determine if you have colorectal cancer.