Mammograms: For 1 life saved, 3 women overtreated

October 29, 2012 by Maria Cheng

(AP)—Breast cancer screening for women over 50 saves lives, an independent panel in Britain has concluded, confirming findings in U.S. and other studies.

But that screening comes with a cost: The review found that for every life saved, roughly three other women were overdiagnosed, meaning they were unnecessarily treated for a cancer that would never have threatened their lives.

The expert panel was commissioned by Cancer Research U.K. and Britain's department of health and analyzed evidence from 11 trials in Canada, Sweden, the U.K. and the U.S.

In Britain, are usually offered to women aged 50 to 70 every three years as part of the state-funded program.

Scientists said the British program saves about 1,300 women every year from dying of breast cancer while about 4,000 women are overdiagnosed. By that term, experts mean women treated for cancers that grow too slowly to ever put their lives at risk. This is different from another screening problem: false alarms, which occur when suspicious mammograms lead to biopsies and follow-up tests to rule out cancers that were not present. The study did not look at the false alarm rate.

"It's clear that screening saves lives," said Harpal Kumar, chief executive of U.K. "But some cancers will be treated that would never have caused any harm and unfortunately, we can't yet tell which cancers are harmful and which are not."

Researchers estimated that of the more than 300,000 British women aged 50 to 52 offered a mammogram every year, about 1 percent would get unnecessary treatment like chemotherapy, surgery or radiation for a breast cancer that wouldn't ever be dangerous. The review was published online Tuesday in the journal, Lancet.

Some critics said the review was a step in the right direction.

"Cancer charities and public health authorities have been misleading women for the past two decades by giving too rosy a picture of the benefits," said Karsten Jorgensen, a researcher at the Nordic Cochrane Centre in Copenhagen who has previously published papers on overdiagnosis.

"It's important they have at least acknowledged screening causes substantial harms," he said, adding that countries should now re-evaluate their own breast cancer programs.

In the U.S., a government-appointed task force of experts recommends women at average risk of cancer get mammograms every two years starting at age 50. But the American Cancer Society and other groups advise women to get annual mammograms starting at age 40.

In recent years, the British breast screening program has been slammed for focusing on the benefits of mammograms and downplaying the risks.

Maggie Wilcox, a survivor and member of the expert panel, said the current information on mammograms given to British was inadequate.

"I went into (screening) blindly without knowing about the possibility of overdiagnosis," said Wilcox, 70, who had a mastectomy several years ago. "I just thought, 'it's good for you, so you do it.'"

Knowing what she knows now about the problem of overtreatment, Wilcox says she still would have chosen to get screened. "But I would have wanted to know enough to make an informed choice for myself."

Explore further: Mammography is 'imperfect' test

shares

Related Stories

Mammography is 'imperfect' test

October 14, 2011
For women today, turning 40 often brings birthday cake and candles. But it also brings a question: Should I get a mammogram?

Routine mammograms may result in significant overdiagnosis of invasive breast cancer

April 2, 2012
New Harvard School of Public Health (HSPH) research suggests that routine mammography screening—long viewed as an essential tool in detecting early breast cancers—may in fact lead to a significant amount of overdiagnosis ...

Doctors, women should spend more time discussing mammograms

August 9, 2011
Due to changing guidelines concerning when and how often they should first be screened for breast cancer with mammograms, many women are confused. The American Cancer Society recommends women 40 years and older get a mammogram ...

ACR, SBI support updated ACOG recommendations that women begin annual mammograms at age 40

July 20, 2011
The American College of Radiology (ACR) and Society of Breast Imaging applaud and support updated American College of Obstetricians and Gynecologists' (ACOG) recommendations that women begin getting annual mammograms at age ...

Recommended for you

Anti-cancer chemotherapeutic agent inhibits glioblastoma growth and radiation resistance

July 24, 2017
Glioblastoma is a primary brain tumor with dismal survival rates, even after treatment with surgery, chemotherapy and radiation. A small subpopulation of tumor cells—glioma stem cells—is responsible for glioblastoma's ...

New therapeutic approach for difficult-to-treat subtype of ovarian cancer identified

July 24, 2017
A potential new therapeutic strategy for a difficult-to-treat form of ovarian cancer has been discovered by Wistar scientists. The findings were published online in Nature Cell Biology.

Immune cells the missing ingredient in new bladder cancer treatment

July 24, 2017
New research offers a possible explanation for why a new type of cancer treatment hasn't been working as expected against bladder cancer.

Shooting the achilles heel of nervous system cancers

July 20, 2017
Virtually all cancer treatments used today also damage normal cells, causing the toxic side effects associated with cancer treatment. A cooperative research team led by researchers at Dartmouth's Norris Cotton Cancer Center ...

Molecular changes with age in normal breast tissue are linked to cancer-related changes

July 20, 2017
Several known factors are associated with a higher risk of breast cancer including increasing age, being overweight after menopause, alcohol intake, and family history. However, the underlying biologic mechanisms through ...

Immune-cell numbers predict response to combination immunotherapy in melanoma

July 20, 2017
Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.