Risk info helps with screening decision

CT scans may avert deaths

NEW YORK, Feb 28, (RTRS): People make more educated decisions about screening tests when they’re given a personalized assessment of their own risk, rather than one-size-fits-all information, according to a new review of past studies.

Those personalized evaluations take into account factors such as age, race, gender, weight, lifestyle and family history to determine an individual’s chances of developing a certain type of cancer, for example.

The new review paper, published in the Cochrane Library, also covered decisions by parents-to-be about whether to undergo genetic screening for their fetus.

“Knowing your individual risk for a particular health problem may help you make an informed choice about what screening services you might be interested in,” said Dr. Michael LeFevre, co-vice chair of the government-backed US Preventive Services Task Force.

The USPSTF makes recommendations for disease prevention, which are typically gender- and age-specific. But the evidence isn’t always there to make guidelines more personalized than that, he said.

Recommendations

“Over time, what would be ideal is that we’re able to make more specific, individualized recommendations and fewer population recommendations,” added LeFevre, who is also a family doctor at the University of Missouri School of Medicine in Columbia and wasn’t involved in the new review.

For their analysis, researchers looked at 41 studies, including almost 29,000 people, which compared some form of personalized risk assessment with a standard message about the effects of a given screening test.

Some risk assessments gave participants a numerical estimate of their chance of developing a certain condition and others simply separated them into low-, medium- or high-risk groups.

Three studies specifically measured how informed people were after receiving risk information. They found 45 percent of study volunteers in the personalized-risk group made informed choices about screening, compared to 20 percent of those who were given generic risk data.

Other studies showed a trend toward more patient knowledge and a more accurate understanding of screening risks following personalized assessments.

“There is progress in the screening field, which is moving away from just trying to maximize the uptake of screening tests,” said Adrian Edwards, who led the review at Cardiff University in the UK.

Awareness

“There is an awareness that screening tests have both pros and cons, and what we’re wanting and encouraging is for people to make informed choices about whether or not to have the screening tests,” he told Reuters Health.

Edwards gave the example of prostate specific antigen (PSA) testing for prostate cancer.

Recent data from two large studies suggest that about one life will be saved for every 1,300 men screened, he said. But a total of 48 of those 1,300 men will be diagnosed with and treated for cancer with therapies that can cause impotence and incontinence.

Despite the increase in knowledge about screening risks, Edwards said many screening programs broadcast a message that the tests are universally beneficial.

“At the moment, I think the screening programs have made it too simple, too easy,” he said. The researchers said people shouldn’t be afraid to ask their doctors about the potential harms of a given screening test.

LeFevre pointed to resources where people can get personalized risk information, including the National Heart, Lung, and Blood Institute’s online tool for heart disease (http://1.usa.gov/9jL3kK) and the National Cancer Institute’s breast cancer risk calculator (http://1.usa.gov/6eW4G), both based on epidemiological research.

There is still a need for more studies on whether personalized assessments affect how many people ultimately choose to undergo screening, according to Edwards. In his team’s analysis, the assessments were tied to a slightly higher uptake of screening. Cancer deaths: Acalculation based on results from a large lung cancer screening trial projects that 12,000 deaths a year among the highest-risk smokers and ex-smokers in the US could be avoided with a national screening program.

The National Lung Screening Trial, published in 2010, found 20 percent fewer deaths from lung cancer in a group of people at highest risk for the disease when they were screened annually with CT scans, a form of high-resolution X-ray that can spot suspicious lung nodules.

Based on the 8.6 million Americans who would fall into that high-risk category because of a decades-long history of smoking, researchers at the American Cancer Society say in a new study that 12,000 fewer people a year would die of lung cancer if national screening were put in place.

“This is the first paper that attempts to assess the impact of screening on lung cancer cases nationally,” one of the authors, Ahmedin Jemal, told Reuters Health. “Twelve thousand is a lot of cases,” he said.

In the National Lung Screening Trial, current or former smokers between the ages of 55 and 74 who had accumulated 30 “pack-years” of smoking — for example by smoking 20 cigarettes a day for 30 years, or 40 cigarettes a day for 15 years — were considered to be at the highest risk for lung cancer.

The 20 percent reduction in deaths among people in that category in the trial was “a singular, enormous accomplishment” said Larry Kessler, of the University of Washington in Seattle, who studies the diagnostic value of screening technologies.

“That was a pivotal event that should have woken people up,” said Kessler, who also wrote an editorial accompanying the new study in the journal Cancer.

To put a number on the potential benefits demonstrated in the NLST, the American Cancer Society researchers used US census and health survey data to calculate the number of Americans at highest risk for lung cancer.