October 27, 2020
Colorectal cancer screening guidelines: What to know
BY Clayton Boldt and Meagan Raeke
The U.S. Preventive Services Task Force (USPSTF) released a new draft colorectal cancer screening recommendation today, lowering the age for average-risk adults to begin screening from 50 to 45. The draft recommendation will undergo further review before it’s finalized, but the lower screening age is consistent with the change the American Cancer Society made to their colorectal cancer screening guidelines in 2018.
These changes come in response to scientific studies that show the rates of colorectal cancer continue to increase among younger adults.
We spoke with our Y. Nancy You, M.D., to learn more about the new guidelines and what they mean.
Why is it significant that another national organization now recommends lowering the age for colorectal cancer screening?
The American Cancer Society and USPSTF are two of the major groups that set the standard for cancer screenings in the U.S. Patients and doctors look to these national organizations for guidance on cancer screening exams. Insurance providers, including Medicare, use their guidance to determine which screening exams are covered as preventive services.
I think we’ll see more doctors recommending the lower age and more 45-year-old patients scheduling their first colonoscopy if both groups have consistent guidelines about the age to begin screening.
Why do you think they have made this change?
I think there are several motivations for this change. First of all, there has been strong evidence over the past few decades for an increasing colorectal cancer rates among young adults ages 18 to 50, especially for rectal cancers, which are more complicated to treat. There is also strong evidence these trends will continue over time.
Additionally, there is a strong desire and a high level of motivation to reduce premature deaths from colorectal cancer. Almost 70% of colorectal cancers diagnosed below age 50 are already stage III or IV, meaning the cancer has spread to the lymph nodes or beyond. When the disease is diagnosed at earlier stages, current treatment options are more successful.
How does the updated recommendation address cancer disparities, particularly among Black Americans?
Black Americans are more likely to be diagnosed with and die from cancer than other ethnicities. These disparities are found across several of the most common cancer types, including colorectal cancer. While there are many reasons for this, several studies have identified lower screening rates among Black Americans as an important factor.
The USPSTF has already recommended that Black Americans start colorectal cancer screening at age 45, a younger age than the general population, in an effort to decrease the disparities seen. They have now reinforced this recommendation and extended it to everyone. Lowering the recommended screening age is an important step to help us make an impact on colorectal cancer disparities by finding and treating cancer at earlier stages.
What recommended screening tests are available for colorectal cancer, and how do they differ?
There are two main types of screening tests for colorectal cancer -- stool-based tests and direct visual exams.
Stool-based tests include the fecal immunochemical test (FIT), fecal occult blood test (FOBT) and stool DNA tests. These tests do not involve physically looking inside the colon and rectum, and so they are less invasive and less expensive. However, they need to be performed more frequently (every 1 to 3 years) and, if an abnormal result is found, a visual exam is needed to identify what is exactly wrong and suggest a course of follow-up action.
Visual exams, which include the colonoscopy, virtual colonoscopy (CT colonography) and flexible sigmoidoscopy, involve directly examining the inside of the colon and rectum where polyps and other diseases arise. They do involve a certain amount of preparation and an office procedure. They are very safe, but like any procedure, are not risk-free. These are performed less frequently than stool-based tests, generally every 5 to 10 years. If something abnormal were found, further diagnostic or treatment procedures (such as removing a polyp) can be done right away.
What about individuals younger than 45? What should they look out for?
A portion of younger patients with colorectal cancer have a hereditary condition or other medical conditions that increase their risk of this disease. So, it’s important to know your family history and understand associated cancer risks.
Younger adults should also look out for symptoms that may be consistent with colorectal cancer, such as pain, bleeding, altered bowel habits or changes in stool patterns. Don’t be shy about talking to your doctor about your bowels.
Finally, maintain a healthy lifestyle to minimize your colorectal cancer risk. Healthy lifestyle behaviors include eating a plant-based diet, getting regular exercise, maintaining a healthy weight, and avoiding tobacco use and excessive alcohol consumption.
What should people know about colorectal cancer screening during the COVID-19 pandemic?
First, know that it’s safe to schedule your recommended cancer screenings now. Like many other doctor’s offices and hospitals, MD Anderson has implemented extensive COVID-19 protocols and precautions to keep patients and employees safe. These should give you peace of mind about getting your screenings on time rather than putting them off. It’s important to understand that getting your screenings on time can help ensure you get a diagnosis earlier, enabling us to diagnose cancers or precancerous at the earliest stages, when they are more treatable or curable.
Also, learn about the different screening tests that are available. Some stool-based tests can be done at home and do not require an office procedure, but a colonoscopy is the gold standard. Remember, if something abnormal were found on a stool-based test, it needs to be followed up with a diagnostic colonoscopy.
Request an appointment at MD Anderson online or by calling 1-877-632-6789.
It’s important to understand the increase in disease burden and the importance of early diagnosis.
Y. Nancy You, M.D.