The HSE confirmed that there are 3,000 cases of cervical cancer notified in the last 10 years to the National Cancer Registry – but just 1,482 of these cases were reviewed by the national screening programme.
The other 1,500 will now have to be investigated to find out if the women had a smear test and wrongly got the all clear.
In what has been described as a “bombshell”, Health Minister Simon Harris revealed in the Dáil that a “potentially considerable number of cases” where women developed cancer were not subjected to an audit.
It was believed that all existing smear tests were re-examined as a matter of practice if a woman was later diagnosed with cervical cancer.
However, the Serious Incident Management Team (SIMT) sent into CervicalCheck since Vicky Phelan settled her case has discovered that not all cases were examined.
Mr Harris said he did not have “specific figures” but agreed with Fianna Fail’s Stephen Donnelly that it could be in the region of 1500.