Colon-cancer testing should start at 45

Screening for colon cancer should begin earlier, at age 45 instead of 50, due to an increase in colorectal tumours among younger people, the American Cancer Society said recently.

The new guidelines came after research showed a 51% increase in colorectal cancer among people under 50 since 1994, and an accompanying rise in death rates.

“When we began this guideline update, we were initially focused on whether screening should begin earlier in racial subgroups with higher colorectal-cancer incidence, which some organisations already recommend,” said Richard Wender, chief cancer control officer for the American Cancer Society.

Groups known to suffer disproportionately high rates of colon cancer include African-Americans, Alaska natives and American Indians.

“But as we saw data pointing to a persistent trend of increasing colorectal cancer incidence in younger adults, including American Cancer Society research that indicated this effect would carry forward with increasing age, we decided to re-evaluate the age to initiate screening in all US adults.”

The new guidelines do not specify which kind of test people should get, but includes options such as a traditional colonoscopy — which should be done every 10 years — or high-sensitivity stool analysis, which, depending on the type, could be done every year to three years.

Regular screening should continue until age 75, and “clinicians should discourage individuals over 85 from continuing colorectal cancer screening”, because the risk of complications outweighs the benefits at that age, said the report. Experts say it is unclear why colon-cancer rates are on the rise in younger people.

Research shows that adults born around 1990 have twice the risk of colon cancer and four times the risk of rectal cancer as adults born around 1950, who have the lowest risk, said the report in CA: A Cancer Journal For Clinicians, a peer-reviewed journal of the American Cancer Society.

Meanwhile, colon-cancer rates in people older than 55 are declining, largely due to the screening and removal of precancerous polyps.

According to Elena Ivanina, a gastroenterologist at Lenox Hill Hospital in New York, the 51% increase in colorectal cancer among those under age 50 since 1994 is an “alarming” trend.

“The reason for the increase is currently not known but possibly associated with obesity and sedentary lifestyles, heavy alcohol use and chronic inflammatory conditions, which are all on the rise,” said Ivanina.