One twin sister diagnosed with colon cancer while other isn’t as doctor shares theory about rise in young people

A doctor has suggested a potential reason for the rise of colon cancer in young people as one woman was diagnosed with the disease, while her twin sister remained healthy - despite living very similar lives.

Brinlee Luster and her twin sister, Mariela, were raised in the same way, went to the same college, studied the same subjects and even met their now-husbands on the exact same day.

But their lives took very different paths when Brinlee, 21, was diagnosed with stage four colon cancer while studying at Utah State University.

Brinlee Luster was diagnosed at the age of 21 (KSL News Utah)

After suffering from symptoms including 'severe abdominal cramping' and fatigue, Brinlee says the signs were dismissed as stress, anxiety, IBS or a side effect of her birth control.

But after her symptoms became more severe, a colonoscopy revealed stage four cancer.

Brinlee told KSL News: "I don't think anything can prepare you for that moment when you're told you have cancer."

After suffering with the illness at such a young age, many have wondered whether there was a chance that Mariela could also have received the same diagnosis.

However, after also having a colonoscopy, it was discovered that she had a number of polyps, which can sometimes develop into cancer, but are often completely harmless.

"I like to think that she really did save my life in a way because I was headed down that route," said Mariela.

"Having [Brinlee] go through something that I couldn't go through, and I couldn't experience, was just so hard."

Oncologist Dr Mark Lewis, from Intermountain Health, has spoken about the risk of colon cancer in young people and some of the factors that could increase the chances of a diagnosis.

"There really is unfortunately no such thing as too young for colon cancer," he said.

"Antibiotics in childhood and in adulthood can affect the bacteria that line the colon.

"We're being very, very careful about prescribing antibiotics to young people because we do know there is at least a slight increased risk for colon cancer decades later."

Brinlee is now in remission (Instagram/@theportstudio)

Cancer Research UK explains that there are around 44,100 new bowel cancer cases in the UK every year, that's around 120 every day.

Meanwhile, it's the fourth most common cancer in the UK, accounting for 11 percent of all new cancer cases.

Brinlee is now in remission after undergoing 30 rounds of chemotherapy and a number of surgeries. Together with Mariela, the pair have created The Port Studio, selling a line of sweatshirts with access for IV ports, as well as their podcast, Live Today.

If you’ve been affected by any of these issues and want to speak to someone in confidence, contact Macmillan’s Cancer Support Line on 0808 808 00 00, 8am–8pm seven days a week.