Colorectal Cancer: What you need to know
Source: The National Cancer Institute, Mayo Clinic, American Cancer Society, and the National Comprehensive Cancer Network
What is Colorectal Cancer?
Colorectal cancer is a cancer that starts in the colon or the rectum, both of which are parts of the large intestine, located in the lower part of the body’s digestive system. During digestion, food moves through the stomach and small intestine into the colon.
All cancer starts when genes in a cell mutate thereby causing abnormal cells within the body. Colorectal cancer often begins as a growth called a polyp, which may form on the inner wall of the colon or rectum. Some polyps become cancerous over time. Finding and removing polyps via colonoscopies can prevent colorectal cancer.
- Older age.The great majority of people diagnosed with colon cancer are older than 50. Colon cancer can occur in younger people, but it occurs much less frequently.
- African-American race.African-Americans have a greater risk of colon cancer than do people of other races.
- A personal history of colorectal cancer or polyps.If you’ve already had colon cancer or adenomatous polyps, you have a greater risk of colon cancer in the future.
- Inflammatory intestinal conditions.Chronic inflammatory diseases of the colon, such as ulcerative colitis and Crohn’s disease, can increase your risk of colon cancer.
- Inherited syndromes that increase colon cancer risk.Genetic syndromes passed through generations of your family can increase your risk of colon cancer. These syndromes include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer, which is also known as Lynch syndrome.
- Family history of colon cancer.You’re more likely to develop colon cancer if you have a parent, sibling or child with the disease. If more than one family member has colon cancer or rectal cancer, your risk is even greater.
- Low-fiber, high-fat diet.Colon cancer and rectal cancer may be associated with a diet low in fiber and high in fat and calories. Research in this area has had mixed results. Some studies have found an increased risk of colon cancer in people who eat diets high in red meat and processed meat.
- A sedentary lifestyle. If you’re inactive, you’re more likely to develop colon cancer. Getting regular physical activity may reduce your risk of colon cancer.
- Diabetes. People with diabetes and insulin resistance have an increased risk of colon cancer.
- Obesity. People who are obese have an increased risk of colon cancer and an increased risk of dying of colon cancer when compared with people considered normal weight.
- Smoking. People who smoke may have an increased risk of colon cancer.
- Alcohol. Heavy use of alcohol increases your risk of colon cancer.
- Radiation therapy for cancer.Radiation therapy directed at the abdomen to treat previous cancers increases the risk of colon and rectal cancer.
Why Should I Get a Screening?
Colorectal cancer (CRC) is the fourth most commonly diagnosed cancer among adults in the United States. More than 140,000 Americans are expected to be diagnosed with CRC this year. It is the second leading cause of cancer death. And every year, more than 50,000 people die with this disease.
Screenings help find cancer at an early stage before a person has any symptoms. The earlier that abnormal tissue or cancer is found, the easier it may be to treat. By the time symptoms appear, cancer may have already begun to spread.
It is important to remember that your doctor does not necessarily think you have cancer if he or she suggests a screening test. Screening tests are given when you have no cancer symptoms. Screening tests may be repeated regularly.
If a screening test result is abnormal, you may need to have more tests done to find out if you have cancer. These are called diagnostic tests.
When Should I Get a Screening?
The American Cancer Society 2018 guideline for colorectal cancer screening recommends that average-risk adults aged 45 years and older undergo regular screening with either a high-sensitivity stool-based test or a structural (visual) exam, based on personal preferences and test availability. As a part of the screening process, all positive results on non-colonoscopy screening tests should be followed up with timely colonoscopy.
What cancer screening methods are available?
While many methods exist, we will focus on two of the preferred methods.
- Colonoscopies are the gold standard in colorectal cancer screening. A colonoscopy allows your provider to view the entire colon, and biopsy and remove polyps if found.
- The National Comprehensive Cancer Network (NCCN) recommends that average-risk adults have a colonoscopy once every ten years if no abnormalities are found.
- Fecal immunochemical test (FIT) require no pre-test diet or medication changes and sampling can be done in the comfort of your own home.
- NCCN guidelines recommend rescreening in three years if no abnormalities are found.
Looking to schedule a colonoscopy? Find a gastroenterologist near you.