Up to 270 women in the UK could have died of cancer due to a "computer algorithm failure" dating back to 2009 under the NHS' breast screening programme - British health secretary Jeremy Hunt said today.
In a Parliamentary statement, Hunt said nearly half a million women between the age of 68 and 71 were not invited to their final breast screening as a result of the buggy software.
An inquiry is being launched into the full details of what went wrong.
The national breast screening programme, overseen by Public Health England (PHE), screens 2 million people every year. Women between the ages of 50 and 70 receive a screening every three years.
"Earlier this year, PHE analysis of trial data from the service found there was a computer algorithm failure dating back to 2009. The latest estimates I’ve received from PHE is that as a result of this between 2009 and the start of 2018, an estimated 450,000 women aged between 68 and 71 were not invited to their final breast screening," said Hunt.
"At this stage it is unclear whether any delay in diagnosis would have resulted in any avoidable harm or death and that is one of the reasons [for] establishing an independent review."
He said the current estimate based on statistical modelling is that "there may be between 135 and 270 women who had their lives shorten[ed] as a result."
The issue came to light because of an update to the screening IT system to improve data insights. The body then informed Hunt in March that some women were not receiving their invitation to their final screening at the age of 70.
"There are a number of linked causes, [including] issues with the systems' IT and how ages are programmed into it," he said.
"I cannot give all answers today but I can commit [to taking] the necessary steps. I promise will not happen again... [and that we are] united in our resolve to be transparent about what went wrong." ®