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Colonoscopy: Cancer Diagnostics, Therapy, and Prevention

Colonoscopy is a screening procedure that involves a physician—usually a Gastroenterologist—examining the entire length of the rectum and colon with a scope, detecting and removing polyps and other abnormalities, and then biopsying those tissue samples.

Does it top many to-do lists? With that image in mind, not quite. But colonoscopy is considered the gold standard test for colorectal cancer (cancer of the large intestine) and saves lives.

According to the American Cancer Society (ACS), the lifetime risk of getting colorectal cancer is one in 20, and it is the third most common cancer excluding skin cancers. The good news is that, since more people have been getting colonoscopies, the incidence of colorectal cancer has plunged 30 percent in the last decade among those age 50 years or older.

Still, not enough people are getting screened.

Screening Recommendations

Dr. David Cohen, board certified Gastroenterologist, says, “It takes a long time for polyps along the gastrointestinal (GI) tract to grow into a size that can be detected, and then for those benign polyps to transform into cancer. So, in most cases, the interval between colonoscopies can be stretched to just once a decade.” ACS screening guidelines follow that men and women over 50 should get a colonoscopy every 10 years.

“Adjustments are made, however, to start times and frequency of screening for people with certain risk factors,” says Dr. Cohen.

He adds that “colonoscopy is one of the few screening tests available that has indisputable evidence for saving lives.” And yet, approximately 25 percent of Massachusetts residents don’t get colonoscopies as frequently or early as they should, if at all. Without regular colonoscopy, polyps could turn into colorectal cancer. Once symptoms—changes in stool, rectal bleeding, abdominal pain, or unexplained weight loss—develop, the disease is likely in a more advanced and life-threatening stage.

“By testing every 10 years,” says Dr. Mark Robbin, board certified Gastroenterologist, “colorectal cancer can be detected and diagnosed in its early and most treatable stages.” And finding polyps and removing them via colonoscopy can prevent cancer in the first place.

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Risk Factors

Healthy lifestyle behaviors, like eating more fruits, vegetables, and whole grains; exercising regularly; and limiting alcohol and avoiding tobacco, can help prevent colorectal and other forms of cancer. “But colorectal cancer has many unmodifiable risk factors, making regular screening necessary,” says Karen Messier, MSN, RN, AOCN, Oncology Program & Clinical Manager.

The risk is higher among men, adults over 50, people with a family history of the disease, African Americans, people with ulcerative inflammatory bowel disease, and those with type 2 diabetes.


What makes people most reluctant about colonoscopy is the purgative part. Preparations involve forgoing solid foods and taking laxatives before the test to cleanse the colon and rectum. “Inadequate bowel preparation could lead to missed growths or lesions, incomplete procedures, or possible complications,” says Dr. Cohen. “To get a clearer view of the lining of the colon, we now prescribe split-dose bowel preparation, meaning half the laxative dose is consumed the night before the procedure; the remaining half ingested hours before. This two-step process is not only a little easier for the patient to handle, but it better ensures removal of liquids that continuously gather from the small bowel into the colon regardless of fasting or intestinal purging. And this better ensures a successful colonoscopy.”

According to Dr. Sonia Uchman, board certified Gastroenterologist, “As for the test itself, sedation helps to prevent discomfort and most people feel normal once the effects of the sedative wear off.” The test only takes about 30 minutes; slightly longer if polyps are found and need to be removed.

“All things considered,” says Dr. Uchman, “brief and slight unpleasantness every 10 years after age 50 is really the only drawback to colonoscopy, while its capacity for saving lives certainly outrivals that.”

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The Gold Standard

Currently, when it comes to colorectal cancer, there’s no match for the comprehensiveness and life-saving capacity that colonoscopy affords. Patients referred for colonoscopy might perk up to hear terms like “virtual colonoscopy” or “capsule endoscopy,” as x-rays or pill cameras seem like easier-to-swallow alternatives (pun intended). But these options still require purgative preparations. And they have limitations.

Capsule endoscopy, for one, involves swallowing a small, disposable pill camera that sends physicians images of the GI tract, but is really only useful for looking at the esophagus and small intestine.

“Even with purgative preparations to remove colon fluids, pill cameras can’t provide a clear enough view of the colon to be a viable alternative to colonoscopy,” says Dr. Cohen.

Pill cameras as well as virtual colonoscopy, which uses x-ray, CT, or MRI scans, can only identify polyps, and can’t remove them. And virtual colonoscopy can’t detect very small polyps, which traditional colonoscopy can.

“Virtual colonoscopy is generally reserved for patients who can’t tolerate colonoscopy because of technical issues like scar tissue in the pelvis or a very redundant (elongated) colon,” says Dr. Cohen. “Growths or lesions detected with virtual colonoscopy then require either a reattempted standard colonoscopy or referral to a surgeon.”

Other tests like fecal occult blood testing, stool DNA tests, double-contrast barium enema, and flexible sigmoidoscopy have limitations as well, such as not being able to detect or remove certain (or any) polyps. Abnormalities found would nevertheless require colonoscopy for follow up.

“Colonoscopy is therefore regarded as the gold standard test for colorectal cancer because it’s extensive, scanning the entire anatomy of the colon; it’s accurate, providing distinct, detailed images; and it’s the complete package, providing colorectal cancer diagnostics, therapy, and prevention,” says Dr. Cohen.

And it’s something people shouldn’t postpone.

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Colonoscopy at Sturdy

In its commitment to providing area residents with the most sophisticated diagnostics and treatments available for colorectal cancer, Sturdy has a state-of-the-art Endoscopy Suite in which nearly 3,000 colonoscopies are performed each year (though that number should be higher, with greater screening compliance). The suite’s comfortable and modern procedure rooms are equipped with the latest technologies, including high-definition video capability that offers sharp, high-contrast images.

Additionally, Attleboro Gastroenterology Associates (AGA), part of Sturdy Memorial Associates, provides evaluation of gastrointestinal function and treatment for disorders. Comprised of board certified Gastroenterologists Drs. Cohen, Robbin, and Uchman, AGA is located at 150 Emory Street in Attleboro and can be reached by calling 508-222-2021.

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