Colorectal cancer found more in younger people, study shows

March 15, 2023

There was a time when physicians were most concerned about people over the age of 55 being diagnosed with colorectal cancer. It was considered “a disease of older people,” said Dr. Arif H. Kamal, chief patient officer for the American Cancer Society and an associate professor of medicine at Duke University’s School of Medicine.

Recent research has shown a trend of increased cases in younger people, a finding confirmed in a study published in the American Cancer Society Journal, “CA: A Cancer Journal for Clinicians.” 

The study, which was released during Colorectal Cancer Awareness Month, finds that the disease is showing up more in people under the age of 50, and often in more advanced stages. In the last three decades or so, cancer rates overall have been declining, but there’s been a 2% increase per year in colorectal cancer among people under the age of 55. 

“It’s mixed news,” Kamal said, “So this catches people’s attention, as it should. It sends the message that we really need to catch it early before it spreads.” 

In 2018, the American Cancer Society recommended that regular colon cancer screenings begin at age 45 for those at average risk, lowering the age from 50 after noting an increase in tumors in younger adults.

“Why it’s happening is sort of an unknown,” Kamal added. Part of the reason, he said, may be related to lifestyle such as lack of exercise, obesity and excess alcohol use, but also the low screening rate for younger people.

He said the colonoscopy rate for people under the age of 50 is about 20%. That’s important because the screenings enable doctors to find and remove pre-cancerous and cancerous polyps, which are small “clumps” of cells. According to the Mayo Clinic, most colon polyps are harmless, but over time some can develop into cancer. Colon polyps often don’t cause symptoms. People may not be aware that the recommended ages for colon cancer screenings has been lowered and that some screening options can be done at home. Additionally, there are factors like the lack of access to gastroenterologists and surgeons in rural areas.

In 2023, roughly 153,020 people nationally are projected to be diagnosed with colorectal cancer with 52,550 dying from the disease, including 19,550 cases and 3,750 deaths in people under the age of 50, according to the study, which is done every three years. In all, more than 1.9 million new cancer cases are expected to be diagnosed in the U.S. in 2023. Most people diagnosed with colorectal cancer will be over the age of 65 still, but 20% will be under the age of 55, according to the study, which is based on information from the National Center for Health Statistics.

In Georgia, the incidence of colon cancer between 2015 and 2019 was 39 out of every 100,000 residents; 38 for non-Hispanic whites; 44 for non-Hispanic blacks; and 36 for Hispanics.

“This is a global trend,” said Dr. Karthi Subbannan , who specializes in oncology and hematology at Northside Hospital. " It’s not anything that’s just here in the U.S. or just in recent years.” She has noticed an increase in younger patients with colorectal cancer in their 30s and 40s at her practice, although the majority are still older.

“Unfortunately, what happens in younger patients is that when they have symptoms like a change in bowels or rectal bleeding, cancer is not the first thing they think about, specifically if they don’t have a family history.”

For women, who often start having mammograms at age 40, the idea of screenings are better accepted. 

AJC release