Colorectal cancer is the third most common cancer among men and women in the United States. The good news, though, is that the cancer is also one of the most preventable.
This type of cancer is largely preventable because it is slow developing. It can take as many as 10 to 15 years for a precancerous polyp to develop into colorectal cancer. During that time, if a polyp is discovered during a colorectal screening, it can be removed.
“The majority of colorectal cancers develop from polyps,” says Matt Graham, M.D., division chief of UT Erlanger Oncology and Hematology. “Identifying polyps at an early stage, when an outpatient colonoscopy to remove them can interrupt the development of colorectal cancer, prevents disease and, ultimately, death.”
Types of colorectal cancer screening
The United States Preventive Services Task Force (USPSTF) recommends colorectal cancer screening for most adults begin at age 50. Through the Affordable Care Act, colorectal cancer screening is covered free of cost under most insurance plans.
You may have heard of colonoscopy, which is the most common form of colorectal cancer screening. During a standard colonoscopy, patients are typically sedated and the rectum and colon are then examined using a flexible, lighted tube called a colonoscope.
“During a colonoscopy, any abnormal growths in the colon or rectum can be removed,” Dr. Graham says. “Studies suggest that colonoscopy reduces deaths from colorectal cancer by about 60 to 70 percent. The USPSTF recommends colonoscopy every 10 years for people at average risk.”
Colonoscopy requires advanced preparation to ensure the colon is thoroughly cleansed so that polyps and other abnormalities can be easily spotted.
Other types of colorectal cancer screening include:
- High-sensitivity fecal occult blood tests—This screening checks for hidden blood in stool samples. These samples are collected by the patient using a kit and then returned to the doctor for testing. The USPSTF recommends this test be repeated annually. If cancer is suspected, additional testing is required.
- Flexible sigmoidoscopy—During this test, a flexible, lighted tube is used to examine the rectum and the portion of the colon nearest to the rectum, called the sigmoid colon. Abnormalities discovered during the screening can be biopsied. Unlike colonoscopy, this type of screening does not examine the entirety of the colon. The USPSTF recommends this screening be repeated every five years and accompanied by a fecal occult blood test every three years.
If abnormalities discovered during screening turn out to be cancerous, several methods of treatment are available, including surgery, chemotherapy, and radiation therapy. A patient’s treatment plan is individualized and based on the location of the cancer and other factors.
The bottom line
“Screening makes a difference, and it should not be delayed,” Dr. Graham says. “It is also important to know your family’s medical history and discuss any cases of cancer with all physicians you see. Screening may be recommended earlier or more often for patients with a strong family history of colorectal cancer or other types of cancer.”
Talk with your physician about what type of colorectal cancer screening is right for you. Don’t have a physician? Find one here.