In response to a rise in cases of colon and rectal cancer among younger adults, the American Cancer Society (ACS) has lowered the age at which it recommends beginning screening for colorectal cancer to 45. The previous recommendation of the ACS was to begin screening at age 50, and several other medical groups still adhere to that standard.
“Compared to 30 years ago, many more people younger than 50 are being diagnosed with colorectal cancer,” says Zev Wainberg, MD, a UCLA oncologist and member of the UCLA Jonsson Comprehensive Cancer Center. Patients sometimes avoid screening because they are nervous about having a colonoscopy, but Dr. Wainberg notes that there now are other less invasive ways to screen, including stool-sample tests and virtual colonoscopy.
Colorectal cancer is the fourth most common cancer and the second-leading cause of cancer death in the United States. The ACS characterizes its guideline to begin screening at age 45 as a qualified recommendation; while there is clear evidence of benefit, the balance of benefits and potential harm, as well as a patient’s values and preferences, should be measured.
Folasade P. May, MD, PhD, a gastroenterologist with the Vatche and Tamar Manoukian Division of Digestive Diseases at UCLA, recommends that patients in their mid-to-late 40s consult with their physicians about the optimal time to begin screening. “Unlike other cancers, this is one that we can prevent in most cases, but people have to take advantage of the screening tools,” Dr. May says. “The jury is still out on whether people at average risk should begin at age 45 or 50, but the most important message we want to convey is that people should definitely start screening by the age of 50 — and earlier for those who are at higher risk,” Dr. Tan says. The gold standard for colorectal cancer screening remains colonoscopy, performed once every 10 years for patients at average risk in whom no precancerous polyps are found. Less invasive tests are available, but they need to be undertaken more frequently — annually or every three-to-five years, depending on the test. A positive result from those tests needs to be followed up with a colonoscopy.
Dr. May explains that patients who are at higher risk for colorectal cancer include those with a parent or sibling who has had colorectal cancer or colon polyps, as well as individuals with inflammatory bowel disease or any hereditary disorder known to cause colon polyps.
Rates for colorectal cancer screening among U.S. adults ages 50-to-75 were only about 65 percent in 2016. UCLA Health has stepped up efforts to screen more eligible patients as part of a national initiative that aims to raise the rate to 80 percent by the end of this year, both by increasing awareness among patients of the importance of screening and by ensuring that physicians counsel their patients on the issue.
“We’ve made major strides, but there is still a great deal of work to be done,” says Dr. May, who has helped spearhead the UCLA Health initiative. “Every year, a new group of patients become eligible to begin screening, and if people are going to start to think about if they should start screening before the age of 50, that means there are many more patients who need to receive this important message. By finding and removing polyps, we can prevent this cancer, and we also have strong evidence that if we find and treat early colorectal cancer, 90 percent of patients can be cured.”