Colorectal Cancer: What Millennials and Gen Zers Need to Know

No one in their 20s, 30s or 40s gets colorectal cancer, right?

Wrong.

The truth is that colorectal cancer is on the rise in young adults and has been for years. That’s why Yale Medicine surgeons are urging people younger than 45—even college students—to talk to their providers about any suspicious symptoms, such as constipation, rectal bleeding, or sudden changes in bowel movements.

Yale Medicine Colon & Rectal Surgery doctors have reported seeing young patients with a diagnosis of colorectal cancer more often. They diagnosed colon cancer in a father of four in his 30s who thought for months that his rectal bleeding was caused by hemorrhoids. In another week, seven patients were seen who were diagnosed; the oldest being 35. The youngest colorectal cancer patient diagnosed in recent months was 18.

In early 2023, the American Cancer Society (ACS) reported that 20% of diagnoses in 2019 were in patients under age 55, which is about double the rate in 1995, and rates of advanced disease increased by about 3% annually in people younger than 50. It predicted that, in 2023, an estimated 19,550 diagnoses and 3,750 deaths would be in people younger than 50. In 2021, both the U.S. Preventive Services Task Force (USPSTF) and the U.S. Multisociety Task Force on Colorectal Cancer, two groups that provide preventive guidelines, recommended that most Americans be screened for colorectal cancer at age 45—five years earlier than previously recommended—and continue with screenings periodically until age 75.

“We are seeing a clear uptick in colorectal cancer in younger generations,” says Haddon Pantel, MD, a Yale Medicine colorectal surgeon.

While colorectal cancer is still most frequently diagnosed in people over 65, incidence in that age group is declining, and older people are less likely than those younger than 50 to be diagnosed with advanced disease.

In fact, according to a 2024 report from the ACS, colorectal cancer has moved up from being the fourth leading cause of cancer death in both men and women under age 50 two decades ago to first in men and second in women. (Breast cancer is the leading cause of death in women under 50.)

Even though colorectal cancer is often highly treatable, the diagnosis can be a major ordeal for Generation Z, Millennials, and Generation X, who range in age from their mid-20s to their late 50s. It can interrupt careers and damage personal finances. Young people diagnosed with colorectal cancer may need to make quick, critical decisions about such matters as preserving sperm or eggs in case treatment impacts their fertility.

Why is there an uptick?

Research is unclear why colorectal cancer numbers are rising in young people. Sedentary lifestyle, overweight and obesity, smoking, heavy alcohol use, low-fiber, high-fat diets or diets high in processed meats, and other environmental factors have all been associated with the disease. Family history of colorectal cancer or polyps, and conditions such as inflammatory bowel disease are also risk factors.

When someone is diagnosed with cancer at a young age, people also suspect genetics, but experts have yet to use genetics to explain the surge. The most common genetic condition associated with colon cancer is Lynch Syndrome, which typically involves tumors on the right side of the colon.Yale doctors are seeing a lot of young people whose colorectal cancer seems to be happening sporadically, as opposed to being caused by a particular genetic syndrome, according to Dr. Vikram Reddy, colorectal surgeon. 

Scientists at Yale and elsewhere are trying to learn more. “There may be other genes associated with predisposition for colorectal cancer that have yet to be discovered,” says Jessica DiGiovanna, MS, a licensed certified genetics counselor for the Smilow Cancer Genetics and Prevention Program. There are approximately 20,000 human genes, but scientists have only been able to map approximately one third of these genes to the human condition. For this reason, scientists are still working to identify genes that can help predict a person’s risk for particular diseases.

Meanwhile, researchers have been making progress in such areas as molecular tumor profiling, which analyzes DNA and other biological characteristics of tumor tissue samples. This can help determine treatment decisions.

Should young people get colonoscopies?

Even though colorectal cancer is rising in young people, the incidence is still too low to justify routine colonoscopies. Once a screening test is developed for a disease, it's important to make sure that the number of screenings performed will prevent enough cancers to justify the costs of and risks associated with the tests. 

A colonoscopy is performed with the patient under conscious sedation. The doctor inserts a flexible tube with a light and camera on the end through the rectum to examine the colon. The tube also allows a doctor to remove any polyps (small bumps on the surface of the colon or rectum) that may be precancerous, heading off many cancers before they develop. For that reason, colonoscopy is considered to be one of the biggest reasons for the overall decrease in colorectal cancer.

Even before the most recent screening recommendation updates, experts have been recommending for several years that Black men and women start colorectal screening at age 45, since they are at higher risk. If you have a family history of the cancer, your doctor may recommend colonoscopy screening at 40 or 10 years before the age when your family member was diagnosed. Adults ages 76 to 85 should ask their doctor if they should be screened. 

What can young people do to stay healthy?

Young people—like everyone else—need to communicate with their doctor if they notice any of the following symptoms. 

• Rectal bleeding: This includes blood coming from the rectum, or blood in the stool or in the toilet after a bowel movement.
• Unusual stools: Watch for any changes in the way your stool looks. Keep an eye out for dark or black stools, which may indicate bleeding from a tumor. Talk to your doctor if you have stool that is narrow, thin or ribbon-like, which may signal that a tumor is obstructing your bowels or rectum.
• Changes in bowel movements: Look for loose stool (diarrhea) or constipation (less than three bowel movements a week), especially if the changes last two weeks or more.
• Low energy or tiredness: This could be due to anemia from blood loss. If you are a young woman with chronic anemia that you assume is due to menstrual bleeding, it’s a good idea to explore other causes as well.

Don’t assume anything.

Regardless of your age, if you experience any or all of the above symptoms, contact your Campbell County Health provider at 307-688-6000 and schedule an appointment to discuss next steps in diagnosing the issue. Those who don't have symptoms, but have a family history of colon cancer should also reach out to their provider who may encourage a colonoscopy earlier in age. 

Don’t be afraid of the tests, either. Many people are put off by the preparation for a colonoscopy, which includes taking a strong laxative the day before to clean out the bowels. But colonoscopy is considered the gold standard for diagnosing colorectal cancers, and it saves lives.

To avoid colorectal cancer, consider making the following changes to your lifestyle:

• If you smoke, quit: That includes e-cigs. If you smoke, your risk is higher not only for lung cancers, but for colorectal and other cancers.
• Drink responsibly: The American Cancer Society advises no more than two drinks a day for men and one for women.
• Exercise: You have a greater risk of developing colorectal cancer if you are sedentary. Being more active might lower your risk.
• Lose weight: If you are overweight or obese, you have a higher risk of both developing colorectal cancer and dying from it. This is especially true for colon cancer.
• Consume adequate fiber: You should take in 25 grams of fiber a day to maintain a healthy colon. This means eating more fresh fruit, vegetables, whole grains, beans, and legumes. The typical American diet is 10 to 15 grams of fiber a day. 
   

Source: Colorectal Cancer: What Millennials and Gen Zers Need to Know > News > Yale Medicine