Colorectal Cancer Now Leading Cause of Cancer Death in People Younger Than 50 According to New JAMA Report

Colorectal cancer is cancer that starts in the colon or rectum. In the United States, an estimated 158,850 people will be diagnosed with colorectal cancer and an estimated 55,230 will die from the disease this year.

Colorectal cancer is still most common in adults over age 55, and the average age at diagnosis is 66 years. In this age group, the number of new cases is decreasing every year. But according to the American Cancer Society, the number of people under 50 diagnosed with colorectal cancer has increased by 2.4% every year between 2012 and 2021.

This increase led to a change in screening guidelines. People with an average risk of colorectal cancer should get their first screening at age 45 instead of 50, and those with a family history or symptoms should be screened earlier. This change was recommended by advocacy organizations in 2018 and officially supported by the U.S. Preventive Services Task Force (USPSTF) in 2021. Thanks to this new recommendation, more and more people are getting screened earlier. Since 2018, there has been a 17% increase in colorectal cancer cases for people between age 45 and 49, directly related to the new screening guideline.

Why are people getting colorectal cancer earlier?

The exact reason why younger people are getting colorectal cancer is still unclear. Lifestyle risk factors, such as excess weight, diet, and not enough exercise, have all been linked to an increased risk of colorectal cancer. But that may not be what is driving the increased risk in younger adults.

“The original story around this is that it was related to people being unhealthy, obesity, problems with nutrition, but what we are seeing, particularly in my patient base, is that these are healthy patients. So, it’s not fitting the original story we were telling,” said Dr. Marshall. “I think part of what we need to figure out, as fast as we can, is what is actually going on.”

Dr. Marshall believes the key may lie in the gut microbiome, though pinning down what exactly is affecting it is something that researchers are still working on. The gut microbiome refers to the microscopic organisms found in the digestive tract, including bacteria and viruses. Changes to the microbiome leading to cancer could be related to diet, microplastics, or antibiotics, but more research is needed to find the link between any of these and colorectal cancer.

Hope for answers

Fortunately, campaigns to help raise awareness of early-onset colorectal cancer seem to be working. The American Cancer Society reports that adults aged 45 to 49 are now being screened for colorectal cancer at the same rate as people aged 50 to 79.

Dr. Marshall hopes that the interest will also lead to an increase in research funding. “I think the money being spent to figure out why young people are getting colorectal cancer will teach us many other things about health in general. This is raising the alarm,” he said.

What signs and symptoms of colorectal cancer should young people look out for?

The signs and symptoms of early-onset colorectal cancer are generally the same as they are for colorectal cancer. These include:

A change in bowel habits. These include diarrhea, constipation, narrow stools, and/or feeling like you can’t fully empty your bowels after using the bathroom.

Abdominal discomfort that does not go away. This includes pain, nausea, cramping, bloating, and/or unusual fullness even if you do not eat a large meal.

Rectal bleeding. You may notice blood in the toilet, in your stool, or on toilet paper.

Anemia. Anemia happens when you do not have enough red blood cells or hemoglobin. While anemia can have causes that are not cancer, anemia may be a sign of bleeding inside the body caused by a tumor.

Unexplained weight loss. If you lose weight without trying, this may be a sign of cancer.

If you have any of these symptoms, talk to your doctor right away.

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