“The poor women who are the subjects of this debate … must be utterly confused.
DR. MICHAEL BAUM
8 Apr 2010 The Gazette KATE KELLAND, REUTERS
LONDON – It’s not hard to find a breast cancer survivor who thinks routine mammograms are a good idea. Almost any woman who had a cancerous tumour detected in her breast during a regular screening appointment would probably think the scan saved her life. But that is not always true and an increasingly heated international debate is raging about whether women are getting the right information on the merits, and risks, of mammograms.
The fear is that over-diagnosis – when screening picks up tumours that will never present a problem – may mean many women are undergoing unnecessary radical treatment, suffering the physical and psychological impact of a breast cancer diagnosis that would otherwise not have come up.
While some scientists are locked in battle, slinging accusations at each other of misleading data and conflicts of interest, others say the fight itself is a signal that it’s time for a new and more refined approach to breast cancer screening.
“What really bothers me ... is the poor women who are the subjects of this debate, who must be utterly confused and not know what the hell is going on or what to do,” Michael Baum, the doctor who introduced Britain’s first breast screening program more than 20 years ago, told Reuters. “To carry on regardless is no longer acceptable. I’m trying to find a way out of this mess.”
Low level argument over the merits of mammograms has bubbled for some years, but a political storm blew up in the United States last year when public health officials questioned whether screening for women in their 40s actually saves lives and proposed upping the regular screening age to 50.
Now, in Europe, two recent scientific studies have brought the issue to a head, pitting convinced breast cancer screening supporters against those who say the numbers just don’t add up.
A team of Danish scientists published a study showing that breast cancer screening programs of the type run by health services in Europe, the United States and other rich nations do nothing to reduce death rates from the disease.
A week later, a British team published a study showing a “substantial and significant reduction in breast cancer deaths” due to screening.
The lead researchers on each paper, Stephen Duffy of Queen Mary, University of London, who led the British study, and Peter Gotzsche of the Nordic Cochrane Centre, who led the Danish team, told Reuters they suspected the other of having long-held biases on breast cancer screening that skewed their work.
At the heart of the matter is the issue of over-diagnosis. This is when a mammogram picks up something called ductal carcinoma in-situ, which are cells – often described as “pre-cancerous” or non-invasive – that may progress into life-threatening cancer if left untreated. The problem is, there is also the chance they would never progress or cause a problem, but instead leave the woman to live in blissful ignorance and die years later – but not of breast cancer.