Screening for colorectal cancer at age 45 would prevent deaths, but screening in older adults would do more

Starting routine screening for colorectal cancer at age 45 rather than at age 50 would reduce the number of cancer deaths in the United States by 11,100, according to a new study conducted by researchers at the Faculty of Medicine. Stanford University.

The move would also reduce the number of cancer cases in the country by 29,400 during this period. However, screening for a greater number of older, high-risk adults would prevent nearly three times more diagnoses and deaths at lower cost, the study revealed.

The study models the potential effects of a change made in 2018 to the screening guidelines of the American Cancer Society. Following the increase in the incidence of colon and rectal cancer in people aged 40, the society lowered the recommended age for average colorectal cancer screening from 50 to 45 years. Other groups, including the US Preventive Services Taskforce, are: to investigate whether their screening recommendations should also change.

The change has affected some physicians who fear that screening resources may be distant from high-risk populations. Overall, the incidence of colorectal cancer remains two to 13 times higher in people over 50 compared to younger people.

"This is one of the most important recent changes to the guidelines for colorectal cancer screening, which is a very controversial subject," said Uri Ladabaum, MD, professor of medicine at Stanford. "Our goal was to carry out a traditional cost-effectiveness badysis, but also to examine the possible tradeoffs and the national impact.We wanted to crystallize the qualitative problems into concrete figures, so that people could then have a debate. productive on these same problems. "

The study found that over the next five years, screening at age 45 could reduce the number of cancer cases by 29,400 and the number of deaths by 11,100, with an additional social cost of 10 , $ 4 billion. 10.6 million more colonoscopies would be needed.

In comparison, increasing screening participation to 80% of people aged 50 to 75 would reduce cases by 77,500 and deaths by 31,800 at an additional cost of only $ 3.4 billion, depending on the model. The number of additional colonoscopies needed would be 12 million.

An article describing the work will be published online on March 28 in Gastroenterology. Ladabaum is the main author. Robert Schoen, MD, professor of medicine and epidemiology at the University of Pittsburgh, is the principal author.

Cost versus benefits

The incidence of colorectal cancer in people aged 50 and over decreased by 32% between 2000 and 2013, mainly because of widespread adoption of screening. But rates for people in their 40s have increased by 22%, according to the American Cancer Society.

Doctors have not yet determined what caused this increase, but obesity and diet are likely factors, said Ladabaum, who heads Stanford Health's gastrointestinal cancer prevention program. Care.

"Obesity being such a big problem and difficult to fight, and other potentially ill-defined influencing factors, people are turning to what we know to be able to help mitigate the risks of colon cancer, namely screening, "he said. "That's what brings us to that question."

The new US Cancer Society guidelines, which aim to stem the rise in colon cancer among young people, recommend screening an additional 21 million people.

The new study compares the potential costs and benefits of this approach by modeling five screening strategies, including colonoscopy every 10 years; annual fecal immunochemical tests; and a 45-year sigmoidoscopy followed by further tests in subsequent years.

To evaluate cost-effectiveness, Ladabaum and colleagues calculated the cost of additional screening compared to years gained with or without cancer, a measure known as quality adjusted life years. An intervention is generally considered profitable if it costs less than US $ 100,000 per quality adjusted life year.

The study found that the five strategies offered benefits at acceptable costs when they were started at age 45 rather than at age 50, the cost per additional year of life adjusted for quality. ranging from $ 2,500 to $ 55,900.

"Is screening 45% cost-effective by traditional standards?" The answer is yes, "Ladabaum said. "But the bottom line for me is that it is nuanced.The crucial question is: can we filter young people and at the same time do a better job of screening older and high-risk people?"

Compromises Navigation

Doctors who were reluctant to subscribe to the new recommendations of the American Cancer Society point to the work that remains to be done to screen high-risk individuals. Although the vast majority of colorectal cancer cases occur in people over 50, only about 62% of them participate in screening, despite the goal of the health care community to reduce this to 80%. .

In their study, Ladabaum and his colleagues explored the potential outcomes of resource allocation in different ways. According to the model, initiation of colonoscopic screening at age 45 would require an additional 758 colonoscopies per 1,000 people and result in a reduction of four cancer cases and two deaths per 1,000 people. In comparison, these procedures could be used to screen 231 55-year-olds previously undetected or 342 people aged 65 or older 75 years of age. These options would avoid 13 to 14 cases and six to seven deaths per 1,000 people. They would also save between $ 163,700 and $ 445,800, thanks to the avoided costs of cancer treatment.

"If we are really faced with compromises at the level of society, whether in terms of effort that we can deploy or in terms of colonoscopy supply and colonoscopy distribution by geography, we can debate the question of whether efforts should now target people or whether we should focus on the elderly, "Ladabaum said. "If we can bring everyone in, that's fine, but otherwise screening for seniors and high-risk people is more cost-effective for public health, and it can become emotional and exciting because the death of A cancer at a young age is particularly devastating. "

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Provided by
Stanford University Medical Center