Early-onset colorectal cancer incidence is increasing most rapidly in Western states, where healthy lifestyles are typical, according to a new study published in the Journal of the National Cancer Institute. This goes against the established belief that risk factors such as obesity and physical inactivity have contributed to the rise of colon cancer incidence.
Although colon cancer incidence and death rates are decreasing among Americans over 50, colon cancer in young adults is increasing. According to the Mayo Clinic, ten percent of colorectal cancer cases (11 percent of colon cancer and 18 percent of rectal cancer) occur in individuals under 50. What colorectal cancer causes are being missed?
Geographic Differences and Early Colon Cancer
Researchers at the American Cancer Society and The Ohio State University examined changes in colon cancer incidence and risk factors among Americans under 50 from 1995 to 2015. They organized data by state and ethnicity.
The increase in colon cancer incidence was mainly in Caucasian Americans, and it varied in magnitude across states. In the most recent data decade (2006-2015), colon cancer incidence increased by an average of 1.1 percent per year. Ten states exceeded a 2.5% increase, and six of those states were in the West. Colon cancer incidence increased by 73 percent in Washington and 57 percent in Colorado.
Rebecca L. Siegel, MPH, is the American Cancer Society scientific director of surveillance research and lead author of the study. She observed, "Although early-onset colorectal cancer incidence is currently lowest in Western states and highest in Southern states, consistent with the prevalence of established risk factors, like obesity, physical inactivity, and smoking, this pattern may change because the steepest increases are in Western states.”
Previous research attributed the increase in young-onset colon cancer to limited screening use, lack of recognition of key symptoms and unhealthy habits among the young. However, this new study provides some surprising data. Siegel adds, "This finding suggests that early life exposures in addition to the 'usual suspects ' may be contributing to the rise in early-onset disease. Future studies should explore novel risk factors for colorectal cancer in young adults" (Medical Express).
The Facts About Young-Onset Colon Cancer
Why is young-onset colon cancer such a threat? The answer is: because no one is looking for it. Here are five reasons why young-onset colon cancer is so dangerous:
- Most people assume colon cancer is a disease for the elderly.
- Colon cancer usually has few or no symptoms in the early stages. This means a young person can have colon cancer but feel quite healthy for years. Seventy-one percent of young Americans with colon cancer are diagnosed with advanced disease (stage III or stage IV).
- Most young Americans are unfamiliar with the signs and symptoms of colon cancer like abdominal pain, changes in bowel habits, rectal bleeding, anemia, unexplained weight loss, nausea and vomiting. Many people—including physicians--dismiss blood in the stool as hemorrhoids or infection.
- Young-onset colon cancer tends to be aggressive and form in the distal colon near the rectum, which makes it more challenging to treat. Adults under 55 years are 58 percent more likely to be diagnosed with advanced colon cancer than older people and are more likely to die from the disease.
- Young-onset colon cancer is more likely to be misdiagnosed. About 67 percent of patients reported seeing at least two doctors, and some more than four doctors, before they were diagnosed correctly with colorectal cancer (2018 Young-Onset Colon Cancer Survey).
Who is at Risk of Colon Cancer?
You’re never too young for colon cancer. The best gift you can give yourself and your family is to educate yourself about the risk factors and symptoms of colon cancer.
If you have a family history of colon cancer, or you are experiencing symptoms, call a GI specialist today. Young people with colon cancer symptoms are more likely to wait at least six months to visit their doctor. Click here to find a gastroenterologist in your area.