Unneeded ops prompt rethink on screening
BREAST screening for women under 50 should be scrapped, public health experts say, amid growing evidence that some are receiving unnecessary surgery.
Two University of Otago public health experts have called on health officials to raise the age for free breast screening to 50, as evidence mounts of the harm screening may cause.
They have pushed for more ‘‘honesty’’ about the risks of getting screened, including warning women about ‘‘overdiagnosis’’.
However, the Breast Cancer Foundation said any attempt to discourage women from screening was dangerous.
‘‘I certainly don’t want anyone dying because they weren’t screening earlier,’’ foundation chief executive Van Henderson said.
The academics’ call comes as questions are asked overseas about breast screening, with the Swiss Medical Board recommending earlier this year that its government phase it out altogether.
Caroline Shaw, of Otago University’s department of public health, said support for screening relied heavily on research that was half a century old and would not stand up to today’s more rigorous standards. ‘‘We need to be more honest with what is going on, because I don’t think we are doing anyone any favours at the moment,’’ she said.
Recent studies have found 10,000 women needed to be screened to save one life. Another three would suffer unnecessary invasive treatment.
A study of nearly 90,000 Canadian women, published in the British Medical Journal in February, found that, for women under 50, screening made no difference to the chances of dying from breast cancer. And for every 424 women screened, one was over-diagnosed.
Some studies have even accused health authorities and advocacy groups of being wilfully misleading about the benefits of breast screening.
In New Zealand, Breastscreen Aotearoa spends about $50 million a year screening women between 45 and 69. The number diagnosed with breast cancer has risen steadily to more than 2800 a year in 2011, while the number of deaths remain at roughly 630.
Shaw said healthy women were undoubtedly having unnecessary surgery after being screened. New Zealand was also looking increasingly isolated in continuing to screen women under 50, being out of step with Britain and Australia. ‘‘Even the Americans aren’t recommending screening under 50.’’
However, strong support for screening remains. A Norwegian study published last week found that despite the risk of over-diagnosis, the benefits of screening still outweighed any harm.
Henderson said the weight of evidence was still firmly with early screening, which had been shown to reduce deaths by about 30 per cent. Many objections to screening were based on costs, not lives. It was best to be cautious, she said.