Health News

March 05, 2019

Preventing Colorectal Cancer with Screening Colonoscopies

Colorectal cancer is a cancer that starts in the colon or the rectum. Per the American Cancer Society, 1 in 21 men and 1 in 23 women in the United States will develop colorectal cancer. Colorectal cancer symptoms often appear only after the cancer has grown or spread. That’s why it’s best to be screened before you have any symptoms. Unlike breast or prostate cancer, colorectal cancer, which is so widespread, can be prevented if a polyp is removed before it has time to transform into a cancer. “A polyp removed can be a cancer prevented,” says Dr. Adrienne Forstner-Barthell, a board-certified colon and rectal surgeon who performs screening colonoscopies for Summit Medical Group Arizona patients. “Colorectal cancer screenings save lives by finding precancerous polyps or by detecting cancer early when it is most treatable.”


Research has shown a decrease over the years in colon cancer cases due to the widespread practice of colonoscopy, a procedure that allows for a complete evaluation of the colon. At Summit Medical Group Arizona, we advise people with an average risk for colorectal cancer to get screened starting at age 50.


Q. What is a colonoscopy?
A. It is a procedure where gas is put in the colon while the patient sleeps, and a flexible tube with a light and microscope at the end is passed all 4-6 feet to examine the large intestine or colon. A colonoscopy allows the doctor to find and remove a polyp before it has the chance to develop into a cancer, making this a test for both preventing and early detection of cancer. It also allows doctors to identify medical diseases of the colon that can badly affect health such as ulcerative colitis, Crohn’s disease or irritable bowel syndrome (IBS).


Q. What is the prep like and why is it so important?
A. The prep involves a combination of a liquid fast and strong laxatives, usually by prescription, that clean the colon prior to the procedure. If the colon is emptied fully, it helps increase detection of even small polyps (which resemble skin tags or moles) that may be otherwise be missed.


Q. How will I feel after the procedure?
A. Most patients feel fatigue or experience mild cramping but feel normal later that same day. Some patients, such as those with IBS, can have more severe cramping for 12-24 hours after, from the gas.


Q. There are other noninvasive screening methods to detect colon cancer. Why is a colonoscopy best?
A. There are other tests, such as a stool test for blood or more advanced tests like Cologuard which tests for abnormal DNA in the stool. These tests can give false positives and negatives, that can lead to missed cancers or over testing. Stool tests need to be repeated every 1-3 years and if positive a colonoscopy will need to be done to find the cause of the positive test.


A colonoscopy is not only a screening test but can be a treatment at the same time. During a colonoscopy, if a polyp is detected, it can be removed thus reducing cancer risk. If a colonoscopy shows no abnormalities, it only needs to be repeated every 10 years.

Q. When should I get screened?
A. Summit Medical Group Arizona recommends that screening should begin at age 50 in average risk patients. Anyone with a personal history of colon cancer or other cancers—no later than age 40. Other studies have suggested that non-Caucasian patients should be screened between ages 40-45, as there is a higher rate of polyps in younger patients of color. There is also increased risk for polyp growth in patients who are morbidly obese, and these patients should consider earlier screening.


If you have a relative with cancer in your nuclear family, you should get a colonoscopy no later than 10 years prior to their age of diagnosis or age 40, whichever is younger. Lastly, anyone with new bleeding, change in bowels - i.e. new diarrhea or constipation, abdominal pain or unexplained weight loss should get a colonoscopy.


Q. What are polyps?
A. Polyps are abnormal growths, similar in size to moles or skin tags that are in the lining of the colon. They can be benign, but most are adenomas, which have cancer-potential if not removed at an early stage.


Q. Does diet contribute to the growth of polyps?
A. There is a lot of controversy about diet and polyp growth. Some literature suggests that a diet heavy in red meat and low in fiber can cause polyp growth, and there is a definite increased risk if the patient is morbidly obese. There are also studies that link smoked meat consumption, including bacon and sausage, to increase risk for polyps or cancer. There is some evidence that aspirin or vitamin D could lower polyp growth, but this is constantly changing. In general, I recommend a diet high in fiber and balancing meat consumption with plenty of fruits and vegetables while keeping consumption of smoked meats to a maximum of
two servings per month.