Risk Factors for Early Onset Colorectal Cancer in Males Identified

June 28, 2023 - A study published recently in Cancer Prevention Research identified seven risk factors for early onset colorectal cancer in males under the age of 50, which researchers posit may improve adherence to national screening recommendations for the disease.

The American Cancer Society reports that colorectal cancer is the third most common cancer diagnosed in both men and women in the United States, with an overall drop in diagnoses since the mid-1980s. However, this decrease is found mostly in older populations, while people younger than 50 have seen colorectal cancer incidence rates climb one to two percent per year.

To improve outcomes for these younger populations, the US Preventive Services Task Force (USPSTF) lowered the age at which adults at average risk of colorectal cancer should begin screening from 50 to 45.

To further improve outcomes, researchers developed a model designed to identify risk factors for early onset colorectal cancer in younger males. A key aspect of the study was determining whether the same set of risk factors that apply to older populations would apply to those under 50.

“This study is important because it puts whether, and possibly how, to screen people who are younger than age 45 -- below the age for recommended colorectal cancer screening and have some of the risk factors we identify -- on the table for consideration for screening,” said the study’s lead author Thomas Imperiale, MD, of the US Department of Veterans Affairs, Regenstrief Institute, and Indiana University School of Medicine, in a press release detailing the research.

Imperiale noted that while the absolute risk of colorectal cancer in patients of younger ages is significantly lower than for those aged 45 to 54, working to identify younger individuals at higher risk is crucial to improving outcomes.

“Clinicians might have a discussion with a patient and say that although screening guidelines don't kick in until age 45 and you don't have a family history, you do have some risk factors,” Imperiale explained. “Might you consider a noninvasive screening test? It could be fecal occult blood testing or multi-target stool DNA testing. It doesn’t have to be a colonoscopy. For men younger than 45 who are at higher-than-average risk, doing some type of screening would seem to make sense.”

To build their risk model, the researchers gathered EHR data from 600 individuals with non-hereditary colon or rectal cancer and 2,400 control patients from US Veterans Affairs medical centers. The cohort was comprised of male patients between the ages of 35 and 49.

Using these data, the research team extracted lab values, vital signs, medications, medical history, and sociodemographic and lifestyle factors for use in the model.

The model identified seven factors conveying higher-than-average risk for early onset colorectal cancer in males that the researchers deemed to be both precise and easy to apply in clinical practice: older age (within the 35- to 49-year-old age range); no regular use of non-steroidal anti-inflammatory drugs; no regular use of statins; current alcohol use; first or second degree relative with colorectal cancer; a higher disease burden; and service-connection/copay variable.

“We don’t believe that any of these risk factors, with the exception of service-connection/copay variable, which we believe may be a proxy for income and/or socioeconomic status (and only an approximate one), are unique or specific to the veteran population,” said Imperiale.

Moving forward, the researchers will analyze data to identify risk factors for early onset colorectal cancer in female veterans.

Much recent research has focused on how to tackle colorectal cancer and its impact on population health by mitigating risk and improving screening. Some notable studies have examined the risks associated with ultra-processed food consumption, while others have worked to explore both traditional and experimental screening methods for colorectal cancer.

However, some research has also been devoted to helping patients already diagnosed with the condition.

Last year, Mayo Clinic researchers successfully developed an artificial intelligence (AI) model to improve predictions of recurrence and survival in colorectal cancer patients.

The model leverages a deep learning framework and tumor images to generate prediction parameters associated with cancer recurrence. Using these insights, the research team could accurately predict recurrence-free survival and flag patients who may or may not need chemotherapy or other intensive treatments based on their probability of cancer recurrence.