A mother underwent a double mastectomy after doctors wrongly diagnosed her with an aggressive form of cancer.
Sarah Boyle, 28, was told she had triple negative breast cancer after she had difficulty breastfeeding her baby.
Mrs Boyle underwent chemotherapy and later needed reconstructive surgery before the mistake was noticed, leaving her "traumatised".
The hospital that treated her apologised, saying it was "human error" that led to her being misdiagnosed.
Mrs Boyle, from Stoke-on-Trent, said life had been "incredibly difficult" for her, as well as her husband Stephen, 31, and their two sons since she was told she needed treatment at the end of 2016.
"Being told I had cancer was awful, but then to go through all of the treatment and surgery to then be told it was unnecessary was traumatising," she said.
She went to Royal Stoke Hospital when she noticed her six-month-old son Teddy becoming "very distressed" when she tried to feed him from her right breast.
After a biopsy and a scan, she was told she had breast cancer and was sent for treatment.
"Ultimately the misreporting of the biopsy was a human error," said a spokesperson for the University Hospital of North Midlands NHS Trust (UHNW), which runs the hospital.
Mrs Boyle said her treatment meant she was unable to breastfeed her second son, Louis, who is seven months old, and now she was concerned about future health complications, including "actually developing cancer".
The trust offered an "unreserved apology" to Mrs Boyle and said it "understands how devastating this has been".
It said all cancer diagnoses were reviewed by a second pathologist.
Mrs Boyle is now pursuing a legal claim against the trust, which has admitted liability.
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