Colorectal cancer, the third most commonly-diagnosed cancer in the United States (excluding skin cancers) and second leading cause of cancer-related mortality, is increasingly affecting people in their 20s and 30s, recently published research shows.

Researchers including University of Colorado (CU) Cancer Center members Swati Patel, MD, an associate professor of gastroenterology in the CU School of Medicine, and Jordan Karlitz, MD, a visiting associate professor of gastroenterology, analyzed data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program. Comparing data from 2000 to 2002 with data from 2014 to 2016, researchers found steep increases in incidence of distant colorectal cancer, or cancer that has spread to other parts of the body.

Alarmingly, they found that incidence of colon-only, distant adenocarcinoma increased 49% among 30- to 39-year-olds, and that rectal-only, distant stage increases were steepest among those age 20 to 29, at 133%.

March is Colorectal Cancer Awareness Month, so we recently asked Patel about what these research findings mean for younger adults and when they should consider getting screened for colorectal cancer.

Q&A

What inspired your research? Had you been seeing a trend of younger patients presenting with late-stage colorectal cancer?

As a gastroenterologist, I am witnessing the published trends front and center. We are increasingly seeing young patients diagnosed with late-stage colorectal cancers. These are often patients who have had symptoms, such as rectal bleeding or iron deficiency, for some time and have had delays in evaluation. The delays are likely multi-factorial, but a common story is that medical providers have played a part in delayed referrals for diagnostic testing, such as colonoscopy.

To investigate this issue, our team conducted a study including primary care providers (PCP) from three different healthcare systems and found that only 72% of PCPs always recommend a colonoscopy to evaluate iron deficiency anemia and only 51% always recommend a colonoscopy to evaluate rectal bleeding. This is very concerning and identifies an immense opportunity for us to get the message out that prompt evaluation of symptoms in young patients is critically important to avoid delays in cancer diagnoses.

Is is just late-stage colorectal cancer that is occurring more frequently in people ages 20-29, or all stages?

Colorectal cancer rates are rising in all age groups under age 50 and for all stages. We are seeing a very sharp rise in late-stage cancers in 20- to 29-year-olds, a trend we do not fully understand.

In your research, you note that colorectal cancer burdens are higher in Non-Hispanic Black and Hispanic populations; why is this?

The exact cause of differences observed based on race and ethnicity are unclear. It is certainly well-established that underrepresented groups have inequitable access to health care and face structural racism that may disproportionately impact delays in diagnosis. There are also possible biologic hypotheses, such as epigenetic changes (behavior and environmental changes that affect the way your genes work) that cause colons among non-Hispanic Black individuals to potentially age faster or microbiome differences that may differentially predispose individuals to cancer.

There is a substantial amount of research being done around race and ethnicity, but the immediate mandate for all of us is to expand screening and health services to all populations and to dedicate ourselves to dismantling inequities.

What are the symptoms people should be looking for?

Rectal bleeding and iron deficiency anemia are high-risk signs/symptoms that require prompt colonoscopy in all patients. These symptoms have been associated with a 10-fold increased risk of colorectal cancer compared to those without these symptoms.

Are there earlier screening initiatives for this age group?

No matter how old/young an individual is, they need to speak to their PCP the MOMENT they meet their PCP about colorectal cancer risk. This discussion should include a thorough review of any possible symptoms, such as rectal bleeding, changes in bowel patterns, unexplained abdominal pain, or iron deficiency anemia that require diagnostic testing. This visit should also include a thorough collection of colorectal cancer and colorectal polyp family history. Those with a family history of colorectal cancer or advanced precancerous polyps require earlier and more frequent screening.

For those who are truly average risk – no family history, no symptoms – multiple major professional societies including the United States Preventative Services Task Force, the US-Multi-Society Task Force, and the National Comprehensive Cancer Network have recently decreased the screening age for average risk individuals from 50 to 45. There are multiple screening options available, including non-invasive stool tests or colonoscopy. The best test is the test that gets done and gets done well!

This story was published by University of Colorado Cancer Center on March 23, 2022. It is republished with permission.