Mammograms don't save as many lives as women think

CHICAGO Tue Oct 25, 2011 3:02pm EDT

A doctor exams mammograms a clinic in Nice, south eastern France January 4, 2008.       REUTERS/Eric Gaillard

A doctor exams mammograms a clinic in Nice, south eastern France January 4, 2008.

Credit: Reuters/Eric Gaillard

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CHICAGO (Reuters) - Many women who have survived breast cancer often say it was a mammogram that "saved their life," a powerful testimonial that can encourage other women to get regular breast cancer screening tests.

But what are the chances that the test actually saved a woman's life? Not that great, according to a new analysis published in the Archives of Internal Medicine on Monday.

"The numbers suggest that at most, 13 percent of those diagnosed with breast cancer have been helped. That means the other 87 percent have not been helped," Dr. Gilbert Welch of Dartmouth College, who led the study, said in a telephone interview.

"That is important when we keep hearing these stories from breast cancer survivors," he said.

Welch said women who tell their stories about surviving breast cancer can be a powerful inducement for other women to get tested for breast cancer, and as mammogram technology has improved, the chances are even greater that doctors will find something suspicious.

But early detection for some women may not be much of a benefit, especially if a cancer is slow growing, Welch and colleagues say. And many women may be diagnosed and treated for a cancer growing so slowly it might never have caused any symptoms or threatened their lives.

The findings add new fodder to the simmering debate over the benefits of screening healthy people for cancer. Earlier this month, the government-backed U.S. Preventive Services Task Force recommended that healthy men not get a common blood test for prostate cancer, causing an uproar among cancer specialists who fear more men will die from prostate cancer.

In 2009, the same group recommended that women under 50 not get routine mammograms. For women 50 and older, it recommended the test only every other year, rather than yearly, causing an outcry from breast cancer advocacy groups.

But screening tests have both benefits and risks, says Welch, who views the current debate as positive for patients who are starting to think more about the risks of screening.

An earlier study by Welch found that routine screening for prostate cancer has resulted in as many as 1 million American men being diagnosed with tumors who might otherwise have suffered no ill effects from them.

In the latest study, Welch and colleagues looked to see how much mammography reduces deaths from breast cancer.

They found that for 50-year-old women whose breast cancers were diagnosed by a mammogram, there was a 13 percent chance that the screening test saved her life.

The question, then, becomes how to preserve the benefit of mammogram without exposing so many women to the harms of overdiagnosis -- which include being treated for cancers that might not cause harm, Welch said.

He said breast cancer screening technology has become better and better at spotting tiny cancers on the assumption that the earlier a cancer is detected, the better the chances of cancer survival.

But Welch said as treatments for breast cancer get better, the need for very early diagnosis is less great.

"For years we've been looking harder and harder for cancer. I think the time has come to ask the question, 'What if we looked a little less hard?'"

Dr. Timothy Wilt of the Minneapolis Veterans Administration, who wrote a commentary on the findings in the same journal, said the study gives doctors science-based information to share with patients, who are often influenced by anecdotes.

"Because survivor stories are often so powerful, but inaccurate, they can result in people making healthcare decisions that are not science based and may be wrong," he said.

(Editing by Cynthia Osterman)

(This story was corrected in paragraph 8 to show mammogram recommendations refer to women under the age of 50, not 40)

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Comments (14)
Gulfstate wrote:
I’m really getting sick of these “mammograms” aren’t a good thing articles obviously engineered by the insurance companies that don’t want to pay for them. Are mammograms effective? Yes, they most certainly are. Do they save lives? Yes, they most certainly do. Even if it’s 13%, it sure matters to those people and their families.

If this test was just for a “man’s problem”, would this or the cost be an issue at all? No.

Oct 25, 2011 12:35pm EDT  --  Report as abuse
policywhiz wrote:
This sounds like the Obama Health Care which wants us all to have cheap health care and so what if a few people die. I am sure the death panel will use this study to support them when they quit giving women the care they need and deserve.

Oct 25, 2011 12:36pm EDT  --  Report as abuse
CascaRufio wrote:
What percentage of women that have never gotten a mammogram or any treatment for any type of cancer were found to have died of breast cancer during the autopsy? I have not been able to find this anywhere. There is no way to know how many of the women that were diagnosed and treated for cancer, would have lived longer if they had not been diagnosed and treated. Increased psychological stress can be far more damaging than any disease and can make people more susceptible to disease. The tissue stress both physical and radiological of a mammogram we know for a fact can cause cancer and/or aggravate tiny benign tumors into activity that would have never been a problem. What we don’t know is if mammograms and treatments are helping or hurting more. For any individual it is impossible to say if detection and treatment will extend life or shorten it. Due to the large number of factors there is no way to perform any study that will definitively prove for or against. Mammograms should be presented as an option with both possibilities described equally and leave it up to the patient to decide without bias from the doctor or media. The focus should be on developing detection methods that cannot possibly cause harm such as very low level ultrasound and high sensitivity imagery that require only normal light and radiation levels as exist everywhere.

Oct 25, 2011 1:05pm EDT  --  Report as abuse
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