A guest column by the American College of Physicians, exclusive to KevinMD.com.

According to the Centers for Disease Control (CDC), in 2012, 65% of U.S. adults ages 50-75 were current with screening for colorectal cancer. Almost 28% were never screened. Despite the availability of multiple methods for detecting precancerous polyps or early cancers, the number of people who take advantage of this opportunity to reduce their risk of dying of colorectal cancer is disappointingly low.

There are many explanations for the relatively low uptake of this type of screening. I will not cover all of them but instead focus on a couple over which we have some control and therefore the greatest likelihood of success in increasing the number of our patients who are screened for colorectal cancer.

One major reason for the low numbers is that we have forgotten that there are methods of screening for colorectal cancer other than colonoscopy. I think that a major disservice was done several years ago when one expert proclaimed that sigmoidoscopy was like getting a mammogram of only one breast. Over the years, colorectal cancer screening became synonymous with colonoscopy. Yet two of the older methods that colonoscopy replaced in the minds of most physicians, stool testing and flexible sigmoidoscopy, are proven to reduce mortality from colorectal cancer, perhaps more so than the “gold standard” colonoscopy. Additionally, they are easier to perform and less expensive options.

The most recent cancer screening guideline published by the American Cancer Society (ACS) and a 2008 joint position paper by the ACS and several medical specialty societies list five options for colorectal cancer screening in average-risk individuals. In addition to the three that I mentioned, double contrast barium enema and CT colonography are ways to screen for colorectal cancer. I will not discuss these last two because many of the same barriers to patients’ getting colonoscopies apply to them as well.

My patients who do not have their colonoscopies usually have one or more excuses. “I never got around to scheduling it,” “I’m worried about a perforation” (usually prompted by knowing someone or someone who knows someone who had that complication), “I’ve heard horrible things about the prep,” “I don’t do well with anesthesia,” “I can’t afford to take time out of work,” and “I don’t have anyone to drive me home” are some of the more common ones.

The ACS recommends that we have an informed discussion with our patients about the various options for colorectal cancer screening, with shared decision making on which option is best for that patient. I am guilty, as many of you probably are, of starting out with recommending colonoscopy and focusing on getting patients to agree. If the patient does not have a colonoscopy, I ask again. And again. And again. While that may satisfy someone’s quality measure on recommended cancer screening, it does not get the patient screened for cancer.

Whether you do it the way that the ACS suggests by presenting all the screening options and helping the patient select one, or you recommend colonoscopy first and work from there, remember that flexible sigmoidoscopy and stool testing are still effective ways of screening for colorectal cancer. They address patient resistance to the full bowel prep, sedation, time out of work, and getting a ride home. If cost is an issue, these are less expensive yet very effective screening tools than colonoscopy. Often, patients who refuse to have a colonoscopy are not aware of the other options and many of them will agree to undergo stool testing instead of colonoscopy.

If your patient chooses to screen using a stool test, specifically a high-sensitivity guaiac-based fecal occult blood test (gFOBT), keep in mind that the sensitivity of this option requires adherence to a yearly schedule of testing, and abnormal tests must be followed up with a colonoscopy – no “do overs,” as patients often request. Also, note the following caveat from the multi-specialty clinical guideline (echoed in the ACS guideline): “A single stool sample FOBT collected after digital rectal exam in the office is not an acceptable screening test, and it is not recommended.” This is still a widespread practice. It is not accurate and gives patients (and physicians) false reassurance that reduces the likelihood that the patient will undergo effective screening. It is not better than no screening at all. Don’t do it!

Regardless of how you and your patients approach colorectal cancer screening, it is important that patients follow up. New delivery and payment models that support the use of electronic health records or paper systems to track physician and patient adherence with recommended screening should increase the number of eligible persons who are screened. In my practice, which is a patient-centered medical home, we are monitoring how many of our patients are up to date with their screening. We are also tracking referrals for colonoscopy and reminding patients when it appears that they have not had the procedure. We hope to do the same for stool occult blood tests soon.

The American College of Physicians (ACP) has resources to help you and your patients with colorectal cancer screening. A 2008 In the Clinic reviews the evidence for the screening options and offers suggestions for how to improve adherence. In 2012, ACP published a guidance statement on screening for colorectal cancer that summarizes existing clinical guidelines on colorectal cancer screening. A companion summary for patients is also available.

Yul Ejnes is an internal medicine physician and a past chair, board of regents, American College of Physicians. His statements do not necessarily reflect official policies of ACP.