colorectal cancer
Colorectal cancer: What you need to know
01:10 - Source: CNN
CNN  — 

Adults across the United States are being diagnosed with colon and rectal cancers at younger ages, and now 1 in 5 new cases are among those in their early 50s or younger, according to the American Cancer Society’s latest colorectal cancer report.

The report says that the proportion of colorectal cancer cases among adults younger than 55 increased from 11% in 1995 to 20% in 2019. There also appears to be an overall shift to more diagnoses of advanced stages of cancer. In 2019, 60% of all new colorectal cases among all ages were advanced.

“Anecdotally, it’s not rare for us now to hear about a young person with advanced colorectal cancer,” said Dr. William Dahut, chief scientific officer for the American Cancer Society. For example, Broadway actor Quentin Oliver Lee died last year at 34 after being diagnosed with stage IV colon cancer, and in 2020, “Black Panther” star Chadwick Boseman died at 43 of colon cancer.

“It used to be something we never heard or saw this, but it is a high percentage now of colorectal cancers under the age of 55,” Dahut said.

Although it’s difficult to pinpoint a cause for the rise in colorectal cancers among younger adults, he said, some factors might be related to changes in the environment or people’s diets.

“We’re not trying to blame anybody for their cancer diagnosis,” Dahut said. “But when you see something occurring in a short period of time, it’s more likely something external to the patient that’s driving that, and it’s hard not to at least think – when you have something like colorectal cancer – that something diet-related is not impossible.”

The new report also says that more people are surviving colorectal cancer, with the relative survival rate at least five years after diagnosis rising from 50% in the mid-1970s to 65% from 2012 through 2018, partly due to advancements in treatment.

That’s good news, said Dr. Paul Oberstein, a medical oncologist at NYU Langone Perlmutter Cancer Center, who was not involved in the new report. The overall trends suggest that colorectal cancer incidence and death rates have been slowly declining.

“If you look at the overall trends, the incidence of colon cancer in this report has decreased from 66 per 100,000 in 1985 to 35 per 100,000 in 2019 – so almost half,” Oberstein said.

“Changes in the mortality rate are even more impressive,” he said. “In 1970, which was a long time ago, the rate of colorectal cancer death was 29.2 per 100,000 people, and in 2020, it was 12.6 per 100,000. So a dramatic, over 55% decline in deaths per 100,000 people.”

Colorectal cancer is the second most common cause of cancer death in the United States, and it is the leading cause of cancer-related deaths in men younger than 50.

Dahut said the best way to reduce your risk of colorectal cancer is to follow screening guidelines and get a stool-based test or a visual exam such as a colonoscopy when it’s recommended. Any suspicious polyps can be removed during a visual exam, reducing your risk of cancer.

“At the ACS, we recommend if you’re at average risk, you start screening at age 45,” Dahut said. “Usually, then your subsequent screening is based on the results of that screening test.”

An ‘alarming’ shift to younger ages

For the new report, researchers at the American Cancer Society analyzed data from the National Cancer Institute and the US Centers for Disease Control and Prevention on cancer screenings, cases and deaths.

The researchers found that from 2011 through 2019, colorectal cancer rates increased 1.9% each year in people younger than 55. And while overall colorectal cancer death rates fell 57% between 1970 and 2020, among people younger than 50, death rates continued to climb 1% annually since 2004.