http://news.bbc.co.uk/1/hi/health/6061652.stm


Breast screening 'may harm some'
Concerns have been raised that breast cancer screening might lead to
some women undergoing unnecessary treatment.
Researchers looked at international studies on half a million women.

They found that for every 2,000 women screened over a decade, one will
have her life prolonged, but 10 will have to undergo unnecessary
treatment.

UK experts said women over 50 should go for their breast checks, but a
screening pioneer raised doubts about the programme's future.

The report, published in the Cochrane Library, involved a review of
breast cancer research papers from around the world.

Women invited to screening should be fully informed of both benefits
and harm
Dr Peter Gotzsche, researcher  

The scientists found mammograms did reduce the number of women dying
from the disease.

But they also discovered it was diagnosing woman with breast cancer
who would have survived without treatment, meaning they were
undergoing unnecessary chemotherapy, radiotherapy or mastectomies.

About a fifth of cancers picked up by screening are in the milk ducts
of the breast.

Some of these cancers will progress while others will not - but there
is no way of predicting what will happen.

This means women and doctors have to decide whether or not to risk
doing nothing, or go ahead with treatment which might be unnecessary.

They also revealed a further 200 women out of every 2,000 experienced
distress and anxiety because of false positives - a result that
indicated a cancer was present but was later found to be wrong.

Lead researcher Dr Peter Gotzsche, of the Nordic Cochrane Centre,
said: "Women invited to screening should be fully informed of both
benefits and harm.

"When screening advocates and their organisations produce information
materials, they generally emphasise the benefits and omit information
on the major harms. This needs to be corrected to ensure that women
can give genuinely informed consent before joining a screening
programme."

In 2001, the same authors concluded there was no convincing evidence
that screening programmes reduce mortality from the disease.

NICE referral?

Michael Baum, professor of surgery at University College London who
set up one of England's first screening programme in 1987, told the
Daily Telegraph: "This latest evidence shifts the balance even further
towards harm and away from benefits.

The benefits of breast screening far outweigh the risks
Julietta Patnick, director of the NHS Cancer Screening Programmes  

"If this report stands up, the NHS screening programme should be
referred to the National Institute for health and Clinical Excellence
to decide whether it should be closed down."

But a spokesman for the Department of Health said that, as mammography
was an accepted, evidence-based technology, it would not be
appropriate to refer the screening programme to NICE."

And Professor John Toy, medical director of Cancer Research UK, said:
"Researchers in the field all agree that breast screening saves lives
although they differ in their views about the balance of the pros and
cons.

"Benefits need to be balanced against any disadvantages, as is the
case with all medical treatments.

"Certainly women invited for screening should be made aware of both
potential benefits and downsides - such as possible initial
mis-diagnosis.

"But overall we continue to encourage UK women to participate in the
NHS Breast Screening Programme."

Jeremy Hughes, chief executive of Breakthrough Breast Cancer said:
"When early changes are picked up by screening it is not currently
possible to predict whether or not they will progress and so treatment
is usually offered to prevent breast cancer from developing.

"It's important women are given clear information about their
treatment options. Early detection saves lives. Women over 50 should
not be discouraged from taking up their screening appointments."

And Julietta Patnick director of the NHS Cancer Screening Programmes
said: "The programme saves 1,400 lives every year. Women who are
screened are also less likely to have a mastectomy than those who are
not screened.

"For lives to be saved breast screening must detect cancers in the
early stages. The benefits of breast screening far outweigh the risks
and I would strongly encourage all women to make an informed choice to
attend for screening when invited."

Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/1/hi/health/6061652.stm

Published: 2006/10/18 09:52:18 GMT

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