A breast cancer screening error affecting 450,000 women may have led to hundreds of lives being cut short, health secretary Jeremy Hunt has revealed.

Hunt said that a computer algorithm failure dating back to 2009 had meant that many women aged 68 to 71 were not invited to their final routine screening.

It is not known whether any delay in diagnosis resulted in avoidable death, but it is estimated that between 135 and 270 women had their lives shortened as a result, he said.

The issue was first brought to the attention of the Department of Health and Social Care in January, but was initially thought to pose a “limited” risk to patients. It was escalated to ministers in March by (PHE), with the Government told the error should not be made public to ensure existing screening services were not overwhelmed.

“Earlier this year PHE analysis of trial data from the service found that there was a computer algorithm failure dating back to 2009,” said Hunt. “The latest estimates I have received from PHE is that as a result of this, between 2009 and the start of 2018, an estimated 450,000 women were not invited to their final breast screening. At this stage it is not clear whether any delay in diagnosis resulted in any avoidable harm or death and that is one of the reasons I am ordering an independent review to establish the clinical impact.”

“On behalf of the Government, Public Health England and the NHS, I apologise wholeheartedly and unreservedly for the suffering caused,” he added.

Screening issues

“We are deeply saddened and extremely concerned to hear that so many women have been let down by such a colossal systematic failure,” says Delyth Morgan, chief executive of charity Breast Cancer Now. “That hundreds of thousands of women have not received the screening invitations they’ve been relying upon, at a time when they may be most at risk of breast cancer, is totally unacceptable.

“We know this will unfortunately be incredibly difficult news for many women to hear. PHE will be directly contacting all women affected – we’d urge against panic and encourage anyone concerned that they have missed their screening invitations to contact the PHE helpline directly for further advice.”

Women in the UK between the ages of 50 and 70 are automatically invited for breast cancer screening every three years. The government is currently investigating the pros and cons of screening a wider age group of women between 47 and 73.

This is controversial: although breast screening sounds like a no-brainer, a growing body of research suggests that screening may do more harm than good. The main concerns are false positives and overdiagnosis – detecting and treating small cancers that, if left alone, might in fact regress or grow so slowly as to do no harm.

Read more: Critics say wider breast screening trial ‘unethical’

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