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In Mammogram Debate, Differences Aren't So Big

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When a federally funded task force announced last November that mammograms should be optional for women under 50, the reaction was explosive.

“I’ve been getting a lot of vitriol,” P.J. Hamel, a blogger for The HealthCentral Network, said at the time. “Just people exploding with rage, basically.”

Recent studies have kept the debate going.

One from Norway found a much smaller effect of mammography than earlier studies, even among older women who usually benefit more. Authors say mammography may reduce the breast cancer death rate by only 2 percent.

Another study from Denmark found mammography screening had no effect in reducing breast cancer deaths.

A third study out of Sweden is the most relevant to the U.S. debate over mammography for women under 50. It concludes that regular screening reduces breast cancer deaths by as much as 29 percent -- nearly twice as much as the U.S. Preventive Services Task Force calculates.

So mammography studies are still all over the place. And among both patients and experts, opinions seem polarized.

Patients Divided

“I just can’t believe that anyone would say that people in their 40s shouldn’t be getting mammograms,” says Carol Rabinovitz, a Massachusetts woman who’s convinced that mammograms saved her life.

Rabinovitz scoffs at those who dwell on the downsides of mammography -- such as the false positive tests that send millions of women to needle biopsies that turn out not to show cancer.

“My God! If it is cancer, wouldn’t you want to know?” she says. “And if it isn’t cancer, hooray! And so you were uncomfortable for a minute and a half. I don’t get it. I don’t get the big deal. The downside seems to me to be nonexistent.”

At the opposite pole is Veneta Masson. She’s a former nurse practitioner who became convinced 10 years ago that regular mammograms were worthless.

“There was no strong scientific basis for continuing with doing mammograms,” Masson says. “I thought, ‘Why am I doing this?’ ”

So Masson stopped getting mammograms, even though her sister died of breast cancer. That puts her in a high-risk category.

“I would say that mammography was a worthy attempt to save women’s lives,” Masson says. “But it was a failed attempt. Let’s let it go.”

‘Torn Apart’ By Debate

On the surface, it looks like the experts are also sharply divided. The American Cancer Society still urges women in their 40s to get regular mammograms every year -- despite the task force’s recommendations.

But some of those on either side of the debate aren’t as far apart as you might think. Dr. Otis Brawley, the Cancer Society’s chief medical officer, says he’s “torn apart” by the ferocity of the debate. Especially since a closer look at the data, he says, shows that experts are squabbling about pretty small differences.

“You have the task force estimating that screening all women in their 40s will save 1,200 lives a year,” Brawley points out. “You have the Swedes estimating that screening all American women in their 40s has the potential of saving slightly more than 2,000 lives. There’s only 800 lives’ difference.”

That’s not to say that each of those 800 lives isn’t important. But the real-world difference between one estimate and the other is not all that big. That’s because breast cancer is relatively unusual among women in their 40s, where all the controversy is focused.

Bottom line: Whichever estimate you want to believe, for these younger women, there’s probably a benefit -- but it’s not huge.

Promoting Choice

“That’s why we think it should be in the hands of the woman herself,” says Dr. Ned Calonge, chairman of the Preventive Services Task Force. “As the harms mount and with the relatively small potential benefit, a woman should understand that and make her own decision.”

Calonge notes that those potential harms escalate among women under 50. The Cancer Society says for every 1,000 women in their 40s screened for 10 years, there will be 600 who will be called back for a repeat mammogram for something suspicious, 350 who will get biopsied, and about five who will end up with a diagnosis of breast cancer. And some women might get treated for a cancer that would never have caused a problem.

Calogne deploys another set of numbers to make the point that the mammography benefit, in terms of breast cancer deaths avoided, is not very large.

“If I take 1,000 women age 40, over their lifetimes 30 of them will die from breast cancer if we do no screening,” he says. “If I screen every one of those women beginning at age 50 until she’s 74, we reduce the deaths from 30 to 23. And if I reach down and screen them in their 40s, I can increase that by one additional life saved -- at best.”

A Better Way To Screen

Calonge and Brawley make another important point -- one on which there’s really no controversy.

“We need a better test,” Calonge says. Even a 30 percent reduction in breast cancer deaths -- the finding of the latest Swedish study, which focused on women under 50 -- isn’t good enough.

“I don’t think we should be content with even a 30 percent mortality decrease,” Calonge says.

He notes that Pap smears -- the gold standard of preventive screening tests -- result in a 90 percent reduction in cervical cancer deaths. Colorectal screening yields a 60 percent reduction.

Brawley also laments the shortcomings of screening mammograms. In fact, the Cancer Society, which has been accused of overselling routine mammography, is now talking more about its limitations.

“I get letters from women who have been diagnosed with stage IV disease -- I get several a week -- and these women say, ‘I got a mammogram every year, how could this have happened to me?’ ” Brawley says. “The fact is, mammograms miss a lot of cancers.”

In fact, a National Cancer Institute fact sheet says, “Screening mammograms miss up to 20 percent of breast cancers that are present at the time of screening.”

Staying The Course

“We need something better than mammography,” Brawley says. But that “something” is years away.

Meanwhile, he says, “my message is stay the course, continue getting mammograms, but also, realize mammography is not perfect.”

Many women seem to be getting that message. P.J. Hamel, the Vermont health blogger, says a lot of women aren’t paying much attention to the squabbles among experts.

When she brought up the new studies recently at a monthly get-together of fellow breast cancer survivors, Hamel says, “the reaction is, you know, the scientists can’t agree with one another, and so there’s a lot of eye-rolling and, you know, ‘whatever, we’re just going to continue to get our mammograms.’ ”

It’s not a great tool for detecting breast cancer early, she says, but it’s the best one we have right now. Copyright 2010 National Public Radio. To see more, visit http://www.npr.org/.

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