An Ontario woman who underwent a mastectomy even though she had no cancer says hearing about another victim brought back horrific memories of her own ordeal.

A week after a doctor removed her breast in 2001, Janice Laporte of Sarnia was told she did not have cancer in the first place.

She is one of at least two women confirmed to have had unnecessary mastectomies at Windsor's Hotel-Dieu Grace Hospital.

Laporte came forward after learning last week that Laurie Johnston of Leamington, Ont. had a similar experience. They were both patients of Dr. Barbara Heartwell, a surgeon with 28 years experience. The hospital says she volunteered to temporarily withdraw from surgeries pending its investigation.

In an interview with CTV News Channel, Laporte said hearing about a second woman who underwent unnecessary surgery brought back memories of her own suffering more than eight years ago.

"It was terrible. When I saw Laurie on TV, I just broke down," Laporte said, taking a breath and pausing before continuing.

"I lost it. Everything came back to me. I was reliving my experience because her story is so much like mine. I felt so bad for her."

She said Heartwell told her husband she had the worst cancer she had ever seen, and that Laporte was going to die.

She allegedly told the couple, "He should take me home and get my affairs in order," said Laporte.

"Of course, he was devastated, thinking he was going to get a death sentence for me."

A week later Laporte says Heartwell called her into her office to reveal there was an error.

Laporte said the doctor began to cry after telling her she never needed the mastectomy.

She said she was shocked to hear that the Windsor hospital held a news conference last week to say there was only one victim of an unnecessary surgery.

"When the hospital had a news conference and said this was the first case they were ever aware of, that's when I thought I had to come forward," Laporte said.

The hospital has since announced that an ongoing pathology review has found seven other cases of "concern" at the hospital, five of which involve Heartwell.

The Ontario government announced Thursday that it is conducting an "external review" into the matter.

Laporte said she regrets not coming forward publicly after her own ordeal.

"If I had done it eight-and-a-half years ago, maybe Laurie wouldn't have had to go through this," she said.

Laporte said that since the mistake, she does not undergo any medical procedures without a second opinion.

"I‘ll never accept a one-person opinion anymore," she said.

"I want to see all my records… you have to ask a lot of questions and see the reports."

The hospital says Dr. Heartwell has admitted she misread needle biopsy results confirming that Johnston, who underwent surgery last fall, did not have cancer.

Kathryn Clarke, a spokesperson for The College of Physicians and Surgeons of Ontario said she cannot reveal details on specific cases, but she said if there is evidence to suggest a doctor is incompetent or has engaged in misconduct, there could be a disciplinary hearing.