A woman was diagnosed with stage 3 cancer after doctors told her she simply had a case of food poisoning.

Kara Miller — a 41-year-old from London, England — was watching a morning news broadcast in September 2021 when she saw a health segment urging people to seek medical attention if they were experiencing rectal bleeding. Thinking she may have experienced the symptom, she decided to call her general practitioner.

“I spoke on the phone with someone at my GP surgery and they told me it was hemorrhoids and it was fine,” she told Southwest News Service.

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Kara Miller.Kara Miller / SWNS
Despite being told that it would “go away,” Miller started feeling sick and dealing with gastrointestinal issues in February 2022. She returned to her doctor after dealing with bloating and diarrhea. She was also unable to eat.

“They told me it was probably food poisoning,” she said. But when her symptoms persisted, she pushed harder for answers. “It was only after I said, ‘No, I’m still sick this is not food poisoning’, they said ‘We’ll have a FIT test.’ ”

A FIT (fecal immunochemical test) is an at-home screening that checks a stool sample for hidden blood, which could be a sign of cancer.

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Kara Miller during chemotherapy.Kara Miller / SWNS
When Miller’s test came back positive, she went to a private gastroenterologist. While the results were concerning, her doctor figured that she was too young for a cancer diagnosis.

“He said to me, ‘I can actually see the FIT test and there’s a significant amount of blood in your stool, but it still could be something else, you’re so young,’” she said. “One of the resounding comments throughout that period was that I was too young. I was aware it could be cancer but it just seemed so farfetched to me.”

Out of precaution, Miller underwent a colonoscopy in March 2022. During the procedure, doctors immediately discovered a 6-centimeter tumor.

“The doctor said, ‘I’m going to take a biopsy of this.’ I said, ‘Is it cancer?’ I remember him holding my hand and slightly nodding,” she recalled. “From that moment I went into total shock – I couldn’t believe it, it was an out-of-body experience.”

Kara Miller after surgery.Kara Miller / SWNS
After a biopsy and additional testing, Miller’s doctors confirmed in April 2022 that she had stage 3 colon cancer, which had spread to her lymph nodes. Her first thought was how her symptoms initially weren’t taken seriously.

“I always look back on that moment and it was only a few months before I was diagnosed but for some people it takes them years to be believed,” she said.

Miller began five weeks of a combination of chemotherapy and radiation to shrink her tumor. She then underwent a six-hour surgery to remove it. At the time, she was fitted with a temporary ileostomy — which allows digestive waste to exit through the small intestine via a stoma in the abdomen — and spent Christmas in the hospital before undergoing an additional 12 weeks of chemotherapy.

Nine months later, she underwent reversal surgery for her ileostomy in August 2023 before beginning her “new normal.”

“Whilst I was physically fit, I played netball internationally and I was quite strong. I would say the mental aspect after treatment and everything finished was by far harder for me than physical treatment,” she said.

Kara Miller after treatment.Kara Miller / SWNS
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Three years in remission, Miller — who now works as a cancer rehabilitation specialist — told the outlet that she wanted to share her story in hopes of urging others to advocate for their health.

“One thing I’ve noticed and realized is you have to self-advocate,” she said. “Being aware of cancer symptoms and how they present is really important to be aware of because it could effectively save your life.”

“I feel a great degree of responsibility,” she added. “I’m always wary of giving people medical advice as I’m not a medical professional but I always want to relay my perspective to help in some way.”