Colorectal cancer is the fourth most common cancer, excluding some types of skin cancer, and the fourth leading cause of cancer-related deaths for adults in the United States, according to the Centers for Disease Control and Prevention. Colorectal cancer occurs in the colon or the rectum, and it is often curable if the cancerous polyps are found early. As such, the U.S. Preventive Services Task Force (Task Force) recommends that adults receive regular screening for colorectal cancer at age 45.
This article provides an overview of colorectal cancer, screening tests and other ways to reduce your risk.
Colorectal cancer begins in the tissues of the colon or rectum. Normally, they grow and divide to form new cells. When this process goes wrong, new cells can form before the body needs them or old cells do not die. These extra cells can form a mass of tissue, creating a tumor. Tumors can be benign (noncancerous) or malignant (cancerous). When colorectal cancer spreads outside the colon or rectum, it is usually found in nearby lymph nodes and the liver.
Your risk of getting colorectal cancer increases as you get older. Other risk factors include:
- Inflammatory bowel diseases, such as Crohn’s disease or ulcerative colitis
- A family history of colorectal cancer
- The presence of colorectal polyps (growths on the inner wall of the colon or rectum)
- Tobacco use
- Type 2 diabetes
- Alcohol consumption
- Lack of physical activity
- A diet low in fruit and vegetables
- A low-fiber and high-fat diet or a diet high in processed meats (bacon, hot dogs, etc.)
Testing for Cancer
Screening tests are crucial to find polyps or cancer before symptoms are experienced. Regular screening, beginning at age 45, is the key to preventing colorectal cancer and finding it early. The Task Force recommends that adults ages 45 to 75 be screened for colorectal cancer. It also recommends that adults age 76 to 85 talk to their doctor about screening.
There are several screening tests available, including a colonoscopy, a digital rectal exam and stool tests. Should a test’s results suggest cancer, a complete physical exam and/or a biopsy will likely be recommended.
The most common sign of colorectal cancer is a change in bowel habits, such as having diarrhea or constipation, finding blood in the stool or discovering stools are narrower than usual. Other symptoms include:
- Feeling that the bowel does not empty completely
- Having gas pains or cramps frequently, or feeling full or bloated
- Losing weight for no reason
- Feeling tired constantly
- Nausea or vomiting
The choice of treatment depends on the location of the tumor and the progression of the disease. Typical treatment consists of surgery, chemotherapy, biological therapy or radiation therapy.
The best way to prevent cancer, in general, is to eat well and not smoke. Some factors, such as genetics, cannot be avoided, which is why it is important to be screened. When colorectal cancer is found early, the five-year survival rate is 91%.
If you have any symptoms of colorectal cancer, talk to your doctor to find out what is causing them. Regular screening is the key to preventing this type of cancer. If you’re over age 45, whether you have symptoms or not, be sure to schedule a screening appointment.