Increase in Colorectal Cancer in Under 50s Confirmed Across Many Countries

Increase in CRC in Under 50s Confirmed Across Many Countries

Liam Davenport

May 28, 20190


The significant increase in the incidence of colorectal cancer (CRC) in people younger than 50 years, already reported in the United States, has also been seen in many countries across Europe, as well as Australia, New Zealand, and Canada.  

Three new studies report the same finding of a significant increase in incidence, and the authors say it cannot be attributed to earlier detection.

The increase in CRC in the under 50s in the US has already been noted over the last 2 years, and experts have told Medscape Medical News that this is “an issue screaming for attention.”

However, “not everyone buys into the fact that these increases are real,” commented Reinier G.S. Meester, PhD, Stanford University School of Medicine, Redwood City, California, “so that’s a reason why we did this study.”

Meester and colleagues looked at incidence patterns in almost 30,000 patients with CRC aged 40-49 years diagnosed over a 40-year period in nine US regions.

The findings, published as a research letter in the May 21 issue of JAMA, revealed that, between 1995 and 2015, there were significant increases in CRC cases in this age group, with the greatest increase seen in distant disease, at an increase of 2.9% per year.

This was underlined by a significant rise in the proportion of distant disease cases, from 22% in 1995 to 27% in 2015, that could not be explained by the decrease in the number of unstaged cases over the same period.

This suggests that “there has been a real increase in risk and that the trends do not represent a shift in age at diagnosis attributable to earlier detection,” they conclude.

Increase Also Seen in Europe, Australia, and Canada 

The second study, published online on May 16 in The Lancet Gastroenterology & Hepatology, looked at trends in the incidence of CRC in cancer registries in Australia, Canada, Denmark, Norway, New Zealand, Ireland, and the UK.

The authors, led by Marzieh Araghi, PhD, International Agency for Research on Cancer, Lyon, France, found that, while overall cancer rates decreased or stabilized, there were significant increases in rates of both colon and rectal cancer in several countries among people younger than aged 50 years.

The increase was around 3% per year in Denmark, New Zealand, and Australia for colon cancer, and that for rectal cancer was 3.4% in Canada and 2.6% in Australia.

Highest Increase in Adults Aged 20-29  

In the third study, Manon C. W. Spaander, MD, PhD, Erasmus MC University Medical Center, Rotterdam, The Netherlands, gathered data on over 140 million individuals aged 20-49 years in 20 European countries.