Florida Woman Recovers from Breast Cancer with Trial Vaccine: ‘I Feel Like I Walked on the Moon’

A Florida woman is healthy again just months after being diagnosed with breast cancer, thanks to a new trial vaccine that is showing success against the deadly disease.

Lee Mercker, from Jacksonville, was shocked to learn in March that she had a very early stage of breast cancer, DCIS stage zero.

“I was healthy,” she told Fox 35. “That’s why I was mad. I was stunned, and everyone around me was more mad and more stunned.”

Mercker’s doctors at the Mayo Clinic laid out her options — she could go the typical treatment route, or she could join a new clinical trial for a vaccine that kills off the cancer cells.

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“I signed on the dotted line that day,” she told WLTV.

The vaccine was simply a shot, administered over 12 weeks.

“They always took your blood, you had a physical, they’d make your shot right there on the spot for you,” Mercker said. “It was three shots, all in a row, alternating arms, four shots, two weeks apart.”

“It’s supposed to stimulate a patient’s own immune response so that the immune cells like t-cells would go in and attack the cancer,” Dr. Saranya Chumsri, one of the Mayo Clinic doctors, told WLTV.

And the vaccine quickly worked. Mercker’s doctors said her tumor shrunk, and her immune system went to work to kill the cancer cells.

Mercker also underwent a double mastectomy to ensure that the cancer was fully out of her body, but she’s now doing well, just 7 months after she was first diagnosed. Mercker said she’s amazed at this breakthrough, and hopes the vaccine can help more breast cancer patients.

“I feel like I walked on the moon,” she told Fox 35. “I worked in an industry with tons of women and I saw all kinds of stories, and it’d just be really nice to stamp this [breast cancer] out.”

The Mayo Clinic is testing the vaccine on more patients, including some with stage four breast cancer, and seeing positive results. Another of Mercker’s doctors, Keith Knutson, told Fox 35 that he expects to start testing a vaccine on healthy patients to stop breast cancer from ever forming, a kind of “flu shot against breast cancer.”