The HSE has announced it is to review a small number of cases following media reports about possible instances of cancer misdiagnosis at hospitals in the northeast of the country.
In a statement, the HSE says that earlier media reports were exaggerated and speculative and were likely to cause unnecessary anxiety for some patients and their families.
The statement says the HSE's main concern was to ensure that if any issues over patient care arose, the patients and their families will be the first to be informed.
It said the tests under consideration were carried out over the last number of years and did not relate to breast services, mammograms, ultrasounds, CT scans or MRI scans.
The HSE said outside clinical experts would carry out the review and a decision will then be taken about what, if any, action is to be taken.