- According to an updated guidance statement from the American College of Physicians (ACP), asymptomatic, average-risk adults are encouraged to start screening at age 50 for colorectal cancer.
- Selecting the right age to start screening is important because it allows clinicians to help more patients.
- Choosing the right screening test is also a crucial consideration. Clinicians should discuss the potential benefits and harms of screening.
Asymptomatic, average-risk adults are encouraged to start screening at age 50 for colorectal cancer, according to updated guidelines from the American College of Physicians (ACP). The guidance statement was published in the Annals of Internal Medicine.
ACP’s updated guidelines are intended to help physicians determine the optimal time to screen adults who are at average risk for colorectal cancer and who do not show symptoms.
This guidance statement recommends the following for average-risk, asymptomatic adults:
- Begin screening for colorectal cancer in average-risk, asymptomatic adults at age 50.
- For adults 45 to 49, consider not screening. Clinicians should talk with patients about the pros and cons of screening in this age group.
- Stop screening for colorectal cancer in adults older than 75 years or in asymptomatic, average-risk adults with a life expectancy of 10 years or less.
- Choose a screening test for colorectal cancer, discussing benefits, harms, costs, availability, frequency, and patient values and preferences with the patient.
- Choose among screening tests for colorectal cancer: a fecal immunochemical or high-sensitivity guaiac fecal occult blood test every two years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years, plus a fecal immunochemical test every two years.
- Should not use stool DNA, computed tomography colonography, capsule endoscopy, urine, or serum screening tests for colorectal cancer.
“We know that mortality from colorectal cancer is high,” Dr. Omar Atiq, ACP President, told Medical News Today. “We want to reduce that mortality. Screening can accomplish that in the right population. We believe we can have a positive effect on reducing mortality from colon cancer by screening more people in accordance with the ACP guidelines.”
“All the evidence suggests the best benefit-risk ratio is actually from 65 to 75 but there is also significant benefit from age 55 to 65,” Dr. Atiq stated.
“However, when you go below age 50 the benefit-risk ratio changes because of the relatively low incidence of colon cancer in that population. We did not see good evidence for the relative benefit being overwhelming in that category. Therefore, one of the issues that we want to highlight is increased colorectal screening amongst average Americans at most risk. And in order to do that, we want to be as rigorous and evidence-based as we can so we target the right population.”
Choosing the right screening age will allow clinicians to help more patients.
“When you increase the screening age without good data to show benefit you not only dilute the percentage of patients that you are able to help, but you also increase the number of people you screen who are less likely to benefit and increase their risk,” Dr. Atiq added.
In reference to the second guideline and not screening adults aged 45-49, “the only potential harm using non-invasive tests is false positives leading to unnecessary colonoscopy. Colonoscopy has a very low rate of perforation but perforation is a severe complication which can lead to emergency surgery,” said Dr. Anton Bilchik, Ph.D., surgical oncologist, chief of medicine, and Director of the Gastrointestinal and Hepatobiliary Program at Saint John’s Cancer Institute in Santa Monica, CA.
In addition, “there may be patients who want to be screened outside recommended screening ages,” Dr. Atiq explained. “It is our role as physicans to talk to them about the relative risk and relative benefit. The risk can be bleeding, perforation, discomfort, radiation exposure, false positive findings requiring further unnecessary intervention, depending on the procedure employed.”
For the third guideline and stopping screening for colorectal cancer in asymptomatic average-risk adults older than 75 years or in asymptomatic average-risk adults with a life expectancy of 10 years or less, “it is very unlikely to detect a colon cancer in an adult over age 75 provided regular screening has been performed starting age 50,” Dr. Bilchik explained. “A life expectancy of 10 years or less generally means that a diagnosis of colon cancer by colonoscopy is unlikely to change that life expectancy.”
The ACP recommends that all clinicians talk about the benefits, harms, costs, availability, frequency, values, and preferences with their patients.
“Although colonoscopy is considered the gold standard for screening, there are numerous other screening tests available,” Dr. Bilchik stated. “Stool-based tests may be more accessible, less expensive and much more convenient.”
For screening tests for colorectal cancer (a fecal immunochemical or high-sensitivity guaiac fecal occult blood test every 2 years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years plus a fecal immunochemical test every 2 years), “this is a more cost-effective, convenient approach to early detection of colon cancer. It also reduces the need for more frequent colonoscopies,” Dr. Bilchik explained.
The ACP also advised against using stool DNA, computed tomography colonography, capsule endoscopy, urine, or serum screening tests for colorectal cancer.
“These tests are expensive and can lead to unnecessary colonoscopies because they have a higher rate of false positive results,” said Dr. Bilchik.