The 41-year-old underwent a mastectomy in 2006, 14 months after she was given the all clear for breast cancer when her biopsy was misdiagnosed.
In March 2005 she underwent a biopsy at the Mid-Western Regional Hospital in Limerick to test for suspected breast cancer.
Due to an excess workload in the hospital the sample was sent to Cork University Hospital. The Tipperary mother-of-three was given the all clear.
However 14 months later a second test revealed she had invasive breast cancer and she underwent an immediate mastectomy.
Last month a HSE report concluded the misdiagnosis was a result of an interpretative error.
Unhappy with the findings, Rebecca O'Malley insisted the Minister for Health establish a full and independent inquiry.
Mary Harney agreed to that request and the inquiry will be undertaken by the recently-established Health Information and Quality Authority.
