Colorectal cancer screening by colonoscopy is more beneficial than if it’s done before or after the procedure — a review of the Norwegian and Swedish studies
The paper challenges assumptions about the safety of colonoscopies and may be getting a lot of attention. “I think our findings suggest that colonoscopy is not the magic bullet against colorectal cancer,” Bretthauer says. But, he notes that, with up to a 50% reduction in mortality risk, that’s still more beneficial than almost any other cancer screening tool.
“A colonoscopy will only work if a patient gets one,” says Bret Petersen, a gastroenterologist at Mayo Clinic and president of the American Society for Gastrointestinal Endoscopy, a leading group of GI doctors. Petersen says it’s important to focus on the outcomes of the people who actually underwent the procedure, which was about 42% of participants who all lived in European countries, including Norway and Poland.
The high number of participants who did not get the procedure has been pointed out by the American Cancer Society. “Screening tests are hard to know if it has any value if the majority of people in the study don’t take it,” says Dr. William Dahut. He mentioned the reduction in risk with those who were screened.
The researchers found that from 2011 through 2019, colorectal cancer rates increased 1.9% each year in people younger than 55. And while overall colorectal cancer death rates fell 57% between 1970 and 2020, among people younger than 50, death rates continued to climb 1% annually since 2004.
Some doctors have been quick to point out that the methods used by endoscopists (doctors performing the procedure) have improved, compared to 2009 when the European study began.
The lead author of the study says he’s aware of all the criticism of his paper. But he pushes back against the idea that endoscopists didn’t find the expected levels of polyps. “In the two countries that contributed the highest number of participants, which is Norway and Poland, the detection rate, which is the quality metric for finding polyps, was 30%, which is well above the current threshold for good quality,” says Dr. Michael Bretthauer of the University of Oslo in Norway. The detection rate was much lower in Sweden, which contributed fewer participants to the study, because, he says, not as many people in Sweden have polyps. ” I don’t think that the argument is valid.”
A fecal immunochemical test, called FIT, can detect small amounts of blood in the stool, and is typically done annually. Another option is a combination test — such as Cologuard — which can detect both blood and DNA changes that may come from a cancerous or precancerous polyp in the stool. People who take this option are often told to do the test every three years.
Patients at Kaiser Permanente opt for the FIT tests more commonly. Sometimes, the biggest hurdle is remembering to take the test, so Corley says at Kaiser they mail the stool-based tests to patients and then keep contacting patients, until tests are sent back.
Corley says that each screening approach has its plus and minuses. If the stool test is positive, a colonoscopy will be recommended to remove any polyps. There are small risks of colonoscopies, such as a chance of a tear in the colon or bleeding at the site of a biopsy, as well as side effects from the procedure.
Cancer death rate in the US is second only to Tuberculosis and it is the leading cause of death for men younger than 50.
The report’s findings, including the rise in colorectal cancer in younger adults, are “troubling,” Dr. Joel Gabre, an expert in gastrointestinal cancers at Columbia University Irving Medical Center, said in an email.
The incidence of colon cancer has decreased from 66 per 100,000 to 35 per 100,000 over the last three decades, Oberstein said.
For the new report, researchers at the American Cancer Society analyzed data from the National Cancer Institute and the US Centers for Disease Control and Prevention on cancer screenings, cases and deaths.
Rebecca Siegel, the senior scientific director of research at the American Cancer Society, said that it is alarming to see how rapidly the patient population is changing younger despite the fact that the numbers of people in the population are decreasing. It is surprising that more advanced disease in people of all ages is on the rise and should motivate everyone over the age of 45 to get screened.
The rates of colorectal cancer and deaths in some places of the US were higher than in others. The data showed that these rates were the lowest in the West and highest in parts of the South and Midwest. The incidence of colorectal cancer ranged from 27 cases per 100,000 people in Utah to 46.5 per 100,000 in Mississippi. There were differing death rates for colorectal cancer in Connecticut and Mississippi.
How Early Should You Be Getting screened? An Empirical Analysis of the Recent Advances in Screening in Colorectal Cancers
“The age to start screening was recently decreased to 45, which will help in an effort to screen more people, but we still need to understand more why we are seeing this increase which is something we are actively looking into,” wrote Mendelsohn, was not involved in the new report.
Mendelsohn says she has seen an increase in advanced colorectal cancers and diagnoses among her younger patients, and she says to watch for symptoms such as rectal bleeding, abdominal pain and changes in bowel habits.
Patients and providers need to recognize the symptoms so they can be evaluated quickly. If you are at an age where you should be getting screened, please do it.