Colon cancer screening update: Start earlier, choose the best test


Patients and doctors should discuss all available colon cancer screening options.

The American Cancer Society (ACS) made a landmark announcement in May 2018 when it updated its colon cancer screening guidelines to recommend that people at average risk of the disease start regular screening at age 45 instead of 50. The change was implemented in part because of increased diagnoses in younger adults. In fact, research suggests that people born in the 1990s and later have twice the risk of developing colon cancer and four times the risk of developing rectal cancer compared to people born in the 1950s to 1980s.

The updated guidelines also emphasize another important point: Patients have choices beyond colonoscopy, and they should be empowered to choose a test that they are willing to do. To be most effective at preventing deaths from colon cancer, screening has to be continued at the recommended intervals. However, many people are unaware of their options. It’s up to health care providers and loved ones to start those conversations – even if it feels uncomfortable for some people.

Colon cancer is one of the most preventable cancers, and the path to prevention is straightforward: Get screened regularly based on your level of risk, and choose a screening option that you will commit to do. 

Get screened at 45

Before the update, The American Cancer Society already recommended screening at age 45 for African Americans, the U.S. ethnic group with the highest rate of death from colon cancer. I hope that adhering to the recommended screening schedule will be less confusing for patients and doctors now that people of average risk also are recommended to start at 45. However, because this recommendation is new, not all insurance types have begun to cover screening colonoscopy for younger people at average risk. Before scheduling the test, patients might want to check whether their insurance covers colonoscopy before age 50.

Getting screened at a younger age might allow doctors to detect colorectal cancer sooner, and in some cases, prevent it. However, some people are afraid of what their results might show. I recommend that patients consider the vast benefits of getting screened. Screening lets us either detect cancer or its precursor, the polyp. In cases when a large polyp is found during traditional colonoscopy, it is removed during the colonoscopy to prevent it from becoming cancerous (malignant) down the road, and patients can continue with their normal activities until it is time to screen again a few years later. If screening reveals a cancer, patients can start treatment earlier with a chance for better outcomes.

Colon cancer was the second leading cause of cancer death in Texas in 2017, according to the Department of State Health Services. However, the screening rate in Texas is only about half of what it should be. One reason for this disparity might be our large, growing population. Texas is facing a shortage of doctors, according to a study by the Association of American Medical Colleges. The study says that when it comes to primary care, the state of Texas is at the bottom of the pack, ranking 47th out of the 50 states for having an adequate number of primary care physicians for the population. This creates barriers to care in rural communities and densely populated areas such as Dallas-Fort Worth. As such, it’s vital that doctors maximize their time with patients and empower them to seek screening.

Know your screening options

Colon cancer screening does not always require a doctor’s referral. It’s important for people to be aware of all their screening options so they can choose the test they’re most likely to complete. For example, patients who choose colonoscopy can have a traditional or virtual exam. Both traditional and virtual colonoscopy requires patients to follow a “clear liquids” diet the day before and drink a solution to empty their bowel that night.  

Traditional colonoscopy involves a detailed examination of the rectum and colon to detect and remove polyps. Patients are asleep under a mild sedation during traditional colonoscopy. Every patient is required to have a ride home from the exam and rest the remainder of the day.

Virtual colonoscopy is less invasive. The provider takes a 3-D picture of the inside of the colon using a CT scanner. Patients remain awake for the exam, can drive themselves home, and can return to work or other daily activities immediately after the exam. If a large polyp is found, however, the patient will then need to schedule a traditional colonoscopy. For patients at higher-than-average risk, a doctor should recommend the best options based on those risk factors.

The other recommended screening options for average-risk individuals are stool-based tests, which have also been shown to reduce death from colorectal cancer. Patients can do stool tests at home and bring the samples to the doctor’s office or send them through the mail for laboratory testing. The most common stool-based tests are:

  • Fecal immunochemical tests (FITs), which can detect hidden blood in the stool – a symptom of colon cancer. Patients place a stool sample in a small tube provided by a doctor, and the sample is then tested in a lab.
  • Guaiac-based fecal occult blood tests (gFOBTs) also look for hidden blood in the stool through a chemical reaction. Patients can test their stool with a kit and detailed instructions provided by a doctor.

Both of these tests are convenient and inexpensive. As with virtual colonoscopy, if a problem is found, the person will need to go ahead and have a traditional colonoscopy to look for, and possibly remove, polyps. But, if the results are normal, the person just needs to repeat the test every year. Stool DNA tests are also available to screen for certain genetic material that can be shed by colorectal cancer cells. These tests can be done at home and then mailed into the lab. However, they are much more expensive than FITs and FOBTs and might not be covered by insurance.

Take control of your health

Certain factors can increase a patient’s risk of developing colorectal cancer, such as a family history of the disease, a personal history of cancer or polyps, or a history of inflammatory bowel disease. I encourage patients to talk to their doctors to determine their individual risk factors and adjust their screening schedule and options appropriately.

Doctors can recommend patients get screened, but it’s ultimately up to patients to take control and make the choices that affect their life in the long term. However, family members and friends can be persuasive! Pooling information about community resources and family history can go a long way toward increasing screening rates and decreasing deaths from colon cancer.

To learn more about your screening options or to schedule an appointment, call 214-645-8300 or request an appointment online.