Impact of mass breast cancer screening has been overrated

It has not been shown to affect women’s life expectancy overall, but does increase invasive interventions, say Susan Bewley, Nick Ross and Margaret McCartney of HealthWatch

The announcement that thousands missed out on mammography tests caused distress to many women and their families (Report, 4 May). The implication was that they now risked premature death from cancer. In fact, as many experts have been pointing out, mass screening for breast cancer has not been shown to have any impact on women’s life expectancy overall – but it does increase invasive interventions like mastectomy. This is why Prof Mike Baum, one of the first proponents of mass breast-cancer screening, now opposes it, as does the growing consensus among epidemiologists.

If Public Health England thinks otherwise, it should publish its modelled estimates so scientists and statisticians can check them. In the absence of good evidence it was disgraceful to suggest women died needlessly.

Jeremy Hunt has commissioned a professor of oncology and a cancer charity chief executive to undertake a rapid review but has confined them to narrow terms of reference that keep ministers and their advisers out of trouble. HealthWatch, the charity promoting evidence-based medicine, has long voiced concerns about both the breast screening programme and the associated age-extension trial. Women and their families deserve to have answers about who advised governments on screening policy, what evidence successive ministers were given (and not given), what political pressures were involved, and what monitoring and governance was put in place.

This is not just a question of IT failure but failures of the political system to adapt to new evidence. Mass breast-cancer screening might have seemed a good idea to many at the time but now owes more to politics and fashion than to science.
Prof Susan Bewley Professor of women’s health, King’s College London, and chair of trustees, HealthWatch, Nick Ross President, HealthWatch, Dr Margaret McCartney GP and patron, HealthWatch

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