Colon Cancer Screening Guidelines: 45 Is the New 50, and 85 Is the New 75
When to start colonoscopy?
The US Preventive Services Task Force (USPSTF) has issued an update of its 2016 recommendations for colon & rectal cancer (CRC) screening, for the first time advising that screening for all average-risk adults begin at age 45. This new recommendation is in line with the guidelines issued by the American Cancer Society, which were updated in 2018, to reflect that
colon & rectal cancer is increasingly being diagnosed at a younger age.
The US Multi-Society Task Force (MSTF) — which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy — has also issued a statement supporting lowering the age of initial screening in normal-risk adults to 45, and promised that an update of their 2017 guidelines would include the new recommendation.
Although the various guidelines differ in specifics, all agree on the general proposition that
colonoscopy is the gold standard for screening and detecting the presence of polyps, adenomas, and CRC. A single colonoscopy, for example, has been shown in large cohort studies to be
associated with a 68% reduction in CRC mortality.
Other commonly used acceptable options include fecal occult blood test (Hemoccult) or fecal immunochemical test every year, or stool DNA-FIT (Cologuard) every 3 years.
When to stop colonoscopy?
Although in the past the thinking was to stop offering colonoscopy after the age of 75, the major guidelines are all in agreement that once an individual reaches age 75, the decision about whether to continue screening should be made on a case-by-case basis, depending on the patient's overall health, relative risks, and life expectancy. Researchers from the Massachusetts General Hospital Cancer Center in Boston reported that screening endoscopy for persons older than 75 in otherwise good health can reduce the risk for CRC incidence and CRC-related death by approximately 40%. The researchers also found, however, that screening did not provide a significant survival benefit for individuals older than 75 with cardiovascular disease, diabetes, or 3 or more other serious health conditions. We know that physiological age and chronological age are not always the same, so not every 75-year-old should be treated equally. Also of concern is that false-positive rate of stool DNA-FIT tests increases with age, therefore making this option less accurate as one ages.
It is important to understand that there are still
50,000 people a year dying from colorectal cancer.
The single factor contributing to this is that most of these people are not getting screened at all — it can be up to 40% of the population, depending on what state you live in. It is therefore important that we encourage everyone to be screened.
Although choosing the right method is important, the choices can be overwhelming for some. Presenting colonoscopy first, emphasizing the benefits for higher-risk patients, and if the patients refuse, offering a fecal-based test. Minimizing the number of options makes the conversation feasible, and it is still very responsible.
The single most important take-away message is that we can prevent colon & rectal cancer by encouraging everyone between 45 and 75 to get checked on a regular basis.
