New colorectal cancer screening guidelines mean testing is no longer “one size fits all”
March 8, 2012 | by City of Hope Staff
Doctors generally recommend getting regular colorectal cancer screenings starting at age 50, but newly published screening guidelines underscore the importance of tailoring the screening strategy to individual risk factors.
The American College of Physicians reviewed screening guidelines from several trusted medical organizations and turned them into a simple message: While most people should get tested every 10 years starting at age 50, people considered at high risk for colorectal cancer should start screening at age 40. They should be screened more often than the average patient, too.
The key is for patients to talk to their doctor about their family history and other conditions that might increase their risk for developing colorectal cancer early.
“Patients with a first-degree relative who had colon cancer, or those with multiple second-degree relatives who had colon cancer, need to be screened earlier and more often — every one to five years, depending on the situation — because those who develop cancer progress to a more advanced stage and develop cancer earlier than the general population,” says Donald David, M.D., chief of the Division of Gastroenterology at City of Hope. This is particularly important if these relatives developed cancer when they were younger than 50.
People with ulcerative colitis also need to be screened earlier, and get tested every other year, added David, who serves on the National Comprehensive Cancer Network panel that issues that organization’s recommendations. Fortunately, private insurance and Medicare usually abide by national guidelines and cover earlier and more frequent screenings where appropriate — even waiving co-pays for screenings, he says.
Interestingly, the guidelines also suggest that those older than 75 or who have a life expectancy of less than 10 more years can avoid screening because they’re likely to die of something other than colorectal cancer.
Today, doctors can offer several screening options for patients at average risk. A colonoscopy might be right for some, while a flexible sigmoidoscopy and stool sample tests might be the best choice for others. Physicians usually recommend a full colonoscopy for people at high risk, though.
What about new technology that enables doctors to see inside the colon without inserting a flexible camera into it? Called computed tomography (CT) colonography, the technique examines the colon using CT imaging done from outside the body.
“CT colonography has the disadvantage of a false-positive and false-negative rate higher than standard colonoscopy, as well as a lack of endorsement by any of the expert panels,” David says.
“It is used only if colonoscopy is not possible. Also, the risk of X-ray exposure is a concern.”
He added that DNA testing of stool holds promise as a screening technique. “It may emerge as the next major change in screening for colon cancer given that it is noninvasive,” David says, “but it is still not precise enough yet.”
David sees progress as medical science continues to refine who needs to be tested more often, and who can safely avoid unnecessary screening.
“Before, we were screening the same people over and over again, and not screening the whole population well,” he says. “Now, time intervals between exams for many people have actually been extended, as we have not been finding anything significant in the exams in between.”
City of Hope offers routine colorectal cancer screening. Contact New Patient Services to find out more.