Colorectal cancer is now the most common cancer death among young Americans, according to new data from the American Cancer Society, highlighting the decades-long trend of more people under 50 being diagnosed with and dying from the cancer.
The mortality rate for colorectal cancer — which includes cancers of the colon and rectum caused by a clump of cells called polyps that can turn cancerous — has increased by 1.1% every year since 2005 among people under 50. That pushed it from the fifth most common cancer death in the early 1990s to the first in 2023 for this age group, according to the new data, which will be published in JAMA.
“It’s pretty terrible,” said Dr. James Prieto, a colorectal surgeon with Methodist Healthcare. “We’re starting to see more people in their 30s and 40s. People in their 20s are rare, but we see that too.”
This trend has taken place as the mortality and incidence rates for colon cancer have decreased for older adults, highlighting a generational gap that researchers are still seeking to understand. Furthermore, the mortality rate for other top cancer killers (breast, lung, brain and leukemia) have decreased over the same period for younger Americans.
In Bexar County, colon cancer incidence rates increased by 11% from 2017-2021 for people under 50, according to county-by-county data from the National Cancer Institute, mirroring a steep increase in cases observed across the U.S. around the time the recommended screening age was dropped from 50 to 45 years of age.
Healthcare providers and Bexar County Commissioner Rebeca Clay-Flores, who is recovering from colon cancer she was diagnosed with in 2024, are looking to bring awareness to San Antonio residents around the cancer, prevention and screenings.
“Colorectal cancer is something we need to talk about,” Clay-Flores said. “People used to think these kinds of stereotypes, they think [colon cancer only affects] old people, men, but it affects all races, all genders and all ages.”
Generational differences
When UT Health San Antonio colorectal surgeon Dr. Alicia Logue was in medical school in the late 1990s, colon cancer in younger people was largely seen as genetic, confined to those with strong familial history of the cancer.
In 2010, Logue’s friend from medical school — a neurologist in Mississippi who, like Logue, had just entered her private practice after finishing residency — was diagnosed with stage 4 colon cancer and told she had months to live. It was especially alarming to Logue because her friend was 33, active and full of life, Logue said. She ended up fighting the disease for six years on chemotherapy before passing away at 39.
“That was the first case that set an alarm off in my head,” Logue said. “I started to notice it in my practice in 2014, 2015. [Today], it’s not uncommon at all to see patients in their 30s and 40s. I’ve had one patient that was 22 and one that was 28.”
Although still relatively low, the risk of getting colorectal cancer in your 20s or 30s is increasing. In 2005, about 5% of colon cancer diagnoses were early-onset (diagnosed before age 50). Today it’s 10%. Most of those diagnoses occur in the 40-49 age range.
“The chance that you develop colorectal cancer if you’re born after the year 1990 versus before 1970 is astronomically different,” Logue said. “So that does raise the question of, do we have to treat this different generationally?”
Roughly 150,000 Americans are diagnosed with colorectal cancer every year, making it the third most common cancer among men and women in the U.S. Alongside increasing mortality rates, the cancer’s incidence has grown by about 2% every year since at least the early 2000s.
Bexar County’s colon cancer rate for those under 50 is similar to the national average, according to the 2017-2021 National Cancer Institute data, though local doctors surmised that San Antonio faces greater risks due to dietary and health factors as well as uneven access to preventative screenings.
“These individuals are not only having an increase in incidence of colon cancer, but they’re also being diagnosed at a much later stage,” said Sandeep Patel, chief of gastroenterology at University Health. “And so their mortalities have gone up. It’s very alarming, very concerning.”
Ultra-processed foods, antibiotics and pollution
Researchers don’t have a clear-cut answer to the why behind the alarming trend. But there’s likely several potential factors at play. They include:
- Dietary changes in the U.S. since the 1970s, including the widespread availability of ultra-processed foods filled with sugar, fat and devoid of fiber.
- Extended use of antibiotics during childhood, which boomed in the ‘70s and ‘80s and disrupts the gut microbiome, potentially making the colon more susceptible to cancer.
- An increase in sedentary lifestyles, obesity and diabetes, all risk factors for colorectal cancer.
- Environmental exposure to pesticides and potentially microplastics.
Studies have also found associations between higher consumption of red meat and processed meats and colorectal cancer and decreased risk associated with high dietary fiber and calcium intake. Smoking and alcohol consumption also contribute significantly to an individual’s risk for developing the cancer.
The data “sparks a lot of very enthusiastic debate amongst surgeons and oncologists” about which factors best explain the increase, Logue said. “The reality is, humans are very heterogeneous. I could be exposed to the same toxins and have a very different reaction to it. So realistically, it’s probably multi-factorial.”
With that being said, health care providers often recommend eating a balanced diet with adequate fiber from whole grains, fruits and vegetables, limiting intake of red meat and processed meats, alcohol and sugar; as well as controlling insulin levels, addressing obesity and getting adequate exercise to decrease your chances of developing colon cancer.
For those who have a first-degree relative who have been diagnosed with colon cancer or an otherwise strong familial history of the cancer, providers recommend considering getting screened earlier.
Increasing awareness in San Antonio
One of the biggest challenges with colorectal cancer is that symptoms are often subtle, like changes in bowel habits, stomach cramps, fatigue, blood in stool, and can go unnoticed or dismissed as other ailments for long periods, allowing cancerous polyps to proliferate undetected.
“The number one symptom for colorectal cancer is a change in bowel habits,” Prieto said. “That’s so nebulous. You go for Tex-Mex food and you’re going to have a change in bowel habits.”
Over 60% of colon cancer diagnosed in young patients is already advanced disease (stage three or four), which is more difficult to treat and cure.
“These symptoms usually show up for a number of years before, and they just kind of [get] bypassed,” Prieto added. “And there’s a number of contributing factors to that too, maybe access to care, insurance, education, overall, cultural unwillingness to see their doctor for something they don’t want to talk about.”
There are several screening options available, including relatively inexpensive and noninvasive stool tests or CT scan. The gold standard is a colonoscopy, which can not only find polyps but also remove them and has the highest accuracy rate of any of the tests.
But the procedure is more expensive, requires a not-so-pleasant prep the day before the procedure, and might require someone to take several days from work.
The American Cancer Society lowered the recommended age to start getting screened for colon cancer from 50 to 45 in 2018.
Clay-Flores and University Health doctors like Patel will be hosting informational meetings later this month and in March, which is colorectal cancer awareness month, to inform residents on prevention, symptoms and screening options.
“Our big preach is that colon cancer is prevalent. It’s a problem. It’s on the rise but most importantly, it’s preventable,” Patel said. “The big message is, just see your primary care doctor, get your colonoscopy or alternative diagnostic test to make sure that you’ve been adequately screened. That’s the big message that we’re trying to get out.”
