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Colorectal Cancer Screening and Prevention

1. Guidelines for Screening

Average Risk

Age 45 years or older
No history of adenoma or colorectal cancer
No history of inflammatory bowel disease
No family history of colorectal cancer

● Cancer prevention screening should be done every 10 years, beginning at age 50. Colonoscopy is the preferred test


Colon cancer screening should begin at age 45 years in African Americans

● Patients that decline colonoscopy can be offered;


FIT (fecal immunochemical test for blood or

Flexible sigmoidoscopy every 5-10 years

● Alternative cancer detection tests:

Annual Hemoccult Sensa
Fecal DNA testing every 3 years

Increased risk:
African Americans
Ashkenazi Jews


Personal history:

Adenoma/sessile serrated polyp (see below)
Colorectal cancer
Inflammatory bowel disease (ulcerative colitis, Crohn’s disease)


Family history of colorectal cancer or multiple polyps

Recommendations for screening when family history is positive but evaluation for
hereditary colon cancer predisposition syndromes considered, but not indicated:


• Single first-degree relative with colo-rectal cancer or advanced adenoma diagnosed at age ≥60 years
Recommended screening same as average risk

• Single first-degree with colo-rectal cancer or advanced adenoma diagnosed at age <60 years or two first-degree relatives with colo-rectal cancer or advanced adenomas
Recommended screening: colonoscopy every 5 years beginning at age 40 years or 10 years younger than age at diagnosis of the youngest affected relative

High risk syndromes
Lynch syndrome/Hereditary Nonpolyposis Colorectal Cancer (HNPCC)

Polyposis syndromes

Classical Familial Adenomatous Polyposis (FAP)
Attenuated Familial Adenomatous Polyposis (AFAP)
MLH-associated Polyposis (MAP)
Peutz-Jeghers Syndrome (PJS)
Juvenile Polyposis Syndrome (JPS)
Hyperplastic Polyposis Syndrome (HPP) (rarely inherited)


Referral to gastroenterologist
Referral for genetic counseling

2. Cancer Prevention
Colorectal cancer can largely be prevented by adherence to the above guidelines.
No prospective clinical trial has shown that either a nutritional or pharmaceutical
intervention has reduced the risk of colorectal cancer


Lifestyle changes:

Eat a variety of fruits, vegetables and whole grains
Stop smoking
Exercise most days of the week
Maintain a healthy weight




​​What are the benefits of screening?
Colonoscopy is one of the most effective cancer screening and prevention exams. Colonoscopy enables the removal of precancerous benign (harmless) polyps from the colon before they can develop into cancer. 


At what age and how often should I have screening colonoscopies?
Screening colonoscopy for colorectal cancer is recommended to start at age 50. If there is an increased risk (such as a family history of colon cancer and some other uncommon conditions) colonoscopy is recommended at an earlier age. If the colonoscopy is normal then it should be repeated every ten years. If a polyp is found then screening will be more frequent such as every five years. Colonoscopy can be stopped in most individuals at age 75, or at the latest 85, depending on the person’s state of health.


Are there any problems with the preparation?
Preparation using laxatives is required to clean the colon. Dehydration can occur but is prevented by drinking plenty of water at the time of preparation. 


What questions should I ask the physician who is going to carry out the colonoscopy?     
1. What is the polyp detection rate of the practitioner performing my colonoscopy?     
2. Will I be able to see documentation, such as a picture of the cecum, that my colonoscopy has covered my entire colon? 


How is a colonoscopy done?

After preparation of the colon the evening before the procedure nothing is taken by mouth from midnight before the procedure. Light intravenous sedation is given and a long flexible fiberoptic tube (colonoscope) is used to examine the entire lining of the
colon. If an abnormality is seen during the procedure a biopsy may be taken through the colonoscope. If a polyp is seen it may be removed using a special instrument passed down the colonoscope. Any tissue removed (biopsied) during the procedure is sent to the laboratory to be examined by a pathologist. The result will be ready a few days after the procedure. 


How often are polyps found?
Polyps occur in about 25% of men and 15% of women aged 50 and over who have a
colonoscopy. A rate much lower than this may indicate a less than the physician is not

What are the chances of complications during or after a colonoscopy?
Complications are rare. Less than 1 in a 1000 experience a complication. If it is necessary to remove a polyp then 7 in a 1000 experience a complication. If there is removal of a polyp the risk of perforation of the colon is 1 in a 1000 and bleeding occurs in 5 in a 1000, but only 1-2 in a 1000 required blood transfusion or surgery. 


What will I do after a colonoscopy?
You will be able to eat a light meal. As the intravenous sedation can take variable amounts of time to wear off your doctor may advise you not to drive or possibly not to go to work that day.


Strang Cancer Prevention Institute has developed and updates guidelines for cancer screening and best practices for cancer prevention. Strang is synonymous with cancer screening and prevention. Strang was the first medical facility to introduce the Pap test into clinical practice which has saved millions of women's lives worldwide. Strang was opened by first lady Eleanor Roosevelt in 1933.

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