Mar 2, 2023 - Health

Colorectal cancer rises among those 55 and younger

Share of new invasive colorectal cancer cases and deaths in the U.S. by age group
Data: Siegel, et al., 2023, “Colorectal cancer statistics”; Chart: Axios Visuals

Alarming new findings offer more evidence of a puzzling rise in colorectal cancer in patients under 50 and the challenges of reaching them with timely screening.

Driving the news: Research published Wednesday showed the uptick in new colorectal cases — among the top causes of cancer death in the U.S. — among younger patients as well as an increase in colorectal cancers diagnosed at more advanced stages.

"This is a pretty remarkable outlier because incidence rates for most other cancers are either stable or going down," Arif Kamal, chief patient officer of the American Cancer Society, told Axios.

Details: The research drew on cancer registries from the National Center for Health Statistics and found the proportion of colorectal cancer cases among those younger than 55 years increased from 11% in 1995 to 20% in 2019.

  • While deaths from colorectal cancer dropped by 2% annually between 2011 and 2020 overall, they increased between half a percent and 3% in individuals 50 and younger.
  • About 60% of all new cases were advanced in 2019, compared to 52% in the mid‐2000s and 57% in 1995, before widespread screening.

What they are saying: "Everyone asks why this is happening and the short answer is, we don't know," Robin Mendelsohn, co-director of the Center for Young Onset Colorectal and Gastrointestinal Cancers at Memorial Sloan Kettering, told Axios.

  • Geographic data shows variations in colorectal cancer incidence and mortality tied to lifestyle factors such as smoking, an unhealthy diet, high alcohol consumption, physical inactivity, excess body weight and whether the person has access to health care such as screening, the authors of the report wrote.
  • For instance, there are about 27 cases per 100,000 people in Utah compared to more than 46 cases per 100,000 people in Mississippi. There were an average of about 10 deaths per 100,00o people in Connecticut and nearly 18 deaths per 100,000 people in Mississippi.
  • Even so, that doesn't explain all of the increases doctors are seeing, Mendelsohn said.
  • For example: "When we compared [our patients] to a national cohort without cancer, they were actually less likely to be overweight and obese. Anecdotally, we see patients who are fit and healthy," she said.

Between the lines: Screening rates among people ages 45 to 55 remain stubbornly low despite the U.S. Preventative Services Task Force lowering the recommended screening age from 50 to 45 in 2021, Kamal said.

  • An estimated 7 in 10 U.S. adults aged 50 to 75 are considered up-t0-date on their screening.
  • But a study in Clinical Gastroenterology and Hepatology found the proportion of first-time colonoscopies in 45-to 49-year-olds increased from 3.5% between 2017 and 2018 to 11.6% between 2019 and 2021.

Be smart: This is certainly not a case for everyone to get screening, Mendelsohn said. Rather, it raises important questions about how to better target those who are younger and may be at higher risk, she said.

The bottom line: Those who are 45 and older should get regular screening for colorectal cancer. Regardless of age, patients should understand risk factors, such as a family history or conditions like irritable bowel disease, and see their doctors with concerning symptoms promptly.

  • "It's so important that patients and providers know this is happening.'" Mendelsohn said. "The majority ... will not have cancer, but because we are seeing this increase, it's so important that if you have symptoms, that you be seen by your doctor and that doctors are aware."
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