Women diagnosed with cancer after getting the all-clear from BreastCheck are not being directly informed about internal reviews showing their mammogram X-ray was incorrectly read.
BreastCheck clinical director Prof Ann O'Doherty said the screening service, which offers free mammograms to women aged 50 to 69, had still not adopted a system of open disclosure - where patients are informed of an adverse event. It will not come into effect until early next year.
The failure to alert women of their reviews, after they are notified to BreastCheck as having developed breast cancer, comes in the wake of the CervicalCheck scandal that also led to patients not being told an investigation found they had a wrong smear test result.
Around two in every 1,000 women who have a mammogram with BreastCheck develop an "interval" cancer - between their two yearly screenings - and some 10pc are due to errors, the Oireachtas Health Committee was told. Prof O'Doherty claimed any woman who inquires about her review was given it in full.
"We have a very open policy," she added.
BreastCheck was unable yesterday to tell the Irish Independent how many of these reports it had in stock that have not yet been disclosed.
There is a time lag in carrying out the reviews and BreastCheck so far is up only to 2011 in its look-back.
Members of the committee questioned BreastCheck staff on why it is only now planning to bring in open disclosure when it was HSE policy for the last five years.
Dr Arnie Hill, a cancer specialist in Beaumont Hospital, told the committee once his patient is diagnosed with breast cancer he inquires if she has been through BreastCheck.
If she has, he tells her about the look-back review that will be carried out by the screening service.
However, he said "only 45pc of women request disclosure". They are mostly concerned with their treatment, he added.
It can be the "last thing on their minds" and "rarely taken up".
He described BreastCheck as a "fantastic service", but said that, like all forms of screening, it has limitations.
Prof O'Doherty said while mammography was the best screening test available for early detection of breast cancer, it was neither 100pc sensitive nor specific.
"Not all cancers are detected by screening mammography," she said.
Over the last five years, survival rates from breast cancer have increased from 75pc to 83pc.
"I have no doubt that breast screening has contributed to this together with better symptomatic services. This programme detects seven cancers per 1,000 women screened," she added.
It was important women continue to avail of BreastCheck which saves lives, she stressed.