Increase in Americans under 50 diagnosed with colorectal cancer: Study

Most doctors recommend getting tested after age 50, but that may change.

The number of Americans under the age of 50 being diagnosed with colorectal cancer is increasing at an alarming rate, according to a new study.

Colorectal cancer is the second leading cause of cancer deaths in the U.S. for men and women combined, according to research from the journal Cancer, published by the American Cancer Society.

A new study published in Cancer, and funded by the National Cancer Institute, found that the proportion of the total number of patients diagnosed with colorectal cancer under age 50 has increased from 10% in 2004 to 12% in 2015.

Most doctors recommend that patients start having colon screenings, like colonoscopies, at age 50, but some are calling for testing to begin earlier.

“It can’t be over-emphasized that everyone is at risk for colon cancer, and a healthy lifestyle does not eliminate the need for screening,” Dr. Boone Goodgame, the study's author and assistant professor of medicine at UT Austin, told ABC News. “Since a missed colon cancer [diagnosis] is frequently a death sentence, I will be getting my screening colonoscopy when I turn 45 next year.”

The U.S. Preventive Services Task Force (USPSTF) is an independent, volunteer panel of national experts in prevention who health care providers look to for recommendations of when to screen people for various diseases, including cancer. Their current recommendation is for routine colorectal cancer screening to start at age 50 for people who do not have symptoms or a known family history.

The American Cancer Society recommends starting regular screening at age 45.

Health care providers and insurance companies often defer to the USPSTF recommendations for when to recommend testing.

The USPSTF last updated its colorectal screening guidelines in 2016, and they are currently under review.

“Colorectal cancer screening saves lives,” says Dr. Alex Krist, vice chair of the USPSTF in an interview with ABC News. He added that not enough people are getting screened. “Sadly if you look at national statistics only about 60% of adults who should be screened are getting screened.”

The task force does not make changes without thorough research and performing a systematic and thorough review that “often takes a year or two,” said Dr. Krist. The USPSTF also performs complex “modeling” in which they try to include all the different aspects of screening for colorectal cancer like potential harms, benefits, and costs, according to the group. If these models show that the potential harms of changing the recommended age of colorectal cancer screening from 50 to 45 outweigh any benefit for a person, then there will be no change. “We’re going to look at all the data available,” says Dr. Krist.

"Colon cancer is not limited to older adults,” said Dr. Goodgame. Ultimately people need to avoid unhealthy lifestyle choices that increase the risk of cancer such as “excess weight and obesity, lack of exercise, and diets higher in meats and lower in fruits and vegetables.”

It’s important to talk to your health care provider about how to prevent cancers like colorectal cancer, and when to start getting screened.

Aaron Cook MD, MPH is a third year internal medicine resident working with ABC News.