A mom who thought her old mattress was causing her back and shoulder pain later learned that she had cancer throughout much of her body.

Kimberley Anderson of Dundee, Scotland, was first diagnosed with stage 3 breast cancer in October 2019 after discovering a lump in her left breast while showering, according to Kennedy News and Media.

She underwent chemotherapy and radiation, as well as a mastectomy with reconstruction on her left breast.

“I was told in early 2021 that I was cancer free — after that I kind of forgot about cancer and put it to the back of my mind,” Anderson, 39, said.

Kimberly Anderson.Kennedy News & Media
About two years later, however, the nail technician began experiencing a new series of symptoms.

“In 2023 I started feeling really fatigued, nauseous and I lost a lot of weight,” she recalled. “I was experiencing muscle aches and pains in my shoulders and in my back.”

The mother of one became so exhausted that she needed to nap during the day.

“I was going to the gym — I was living a healthy lifestyle at the time,” she said. “I just didn’t really think the cancer would come back because I had been living quite healthily.”

“I thought I was just getting older, or my mattress was hurting my back,” Anderson added. “It was an oldish mattress — I did actually go and buy a new mattress.”

Anderson on a hike.Kennedy News & Media
However, by August, the pain in her neck had become so severe that she was having trouble breathing and swallowing, prompting her to go to the hospital.

“I was struggling to breathe and swallow at this point so I went to emergency room,” she said.

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Doctors performed a CT scan and discovered an approximately 2-inch tumor in her neck, along with additional masses elsewhere in her body.

“They did a CT scan and I had a … tumor in my neck, a mass on my chest wall, a mass on my ovaries, a mass on my adrenal gland and my ribs,” Anderson said.

Anderson was diagnosed with stage 4 metastatic breast cancer.

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“I started crying and shouting for my partner to come through because I didn’t really know what to do or say,” she recalled.

“It was an absolute shock because I really had put it [the cancer] behind me,” she added. “I thought that chapter of my life was closed and I didn’t want to think about it again.”

The following month, Anderson began five rounds of radiation treatment targeting the tumor in her neck, followed by 12 rounds of chemotherapy.

Anderson during chemo treatment.Kennedy News & Media
Then, in July 2024, she learned the disease had spread to her brain. She underwent surgery that September to remove the brain tumor and now takes oral chemotherapy medication every day.

“The cancer is still present but it’s completely stable, there has been no growth for over a year now,” she explained.

For now, she is focused on continuing the treatment.

Scan of Anderson’s brain showing the tumor.Kennedy News & Media
“I hope that I stay on this treatment for as long as possible,” she said. “When this one does stop working, I’ll move on to a different one and I think that will be my last treatment — I think that’s my last option.”

“I’m really hoping these tablets work for as long as they can,” she added.

Anderson said she has also tried not to dwell on survival estimates.

Anderson during her cancer treatment.Kennedy News & Media
“The statistics before the cancer moved to my brain was that my prognosis was anything between 10 and 20 years, but once it goes to your brain the statistics say that it drops to between three and five years,” she said.

“I don’t believe in these statistics, I don’t take any notice of that,” she continued. “Just because it’s three years on the statistics, it doesn’t mean that it’s three years for me.”

“I’m not just a statistic, I’m stronger than a statistic,” she added.

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Anderson hopes her experience will encourage other women to pay close attention to changes in their bodies and seek medical care when something does not feel right.

“I advocate that women should be checking their breasts no matter what age they are — even if you’re in your 20s,” she said.

“We know our bodies better than anyone, including the doctor, so don’t let a doctor [dismiss you],” Anderson added. “Advocate for yourself, push past the primary care barrier, do what you need to get seen by proper specialists.”