The Importance of Colorectal Cancer Screening: How Early Detection Saves Lives

Colorectal cancer ranks as the second leading cause of cancer-related deaths in the United States. Referred to as a “silent killer” due to its lack of symptoms, colorectal cancer often is not diagnosed until it has progressed to a later stage, making treatment difficult. However, early detection of colorectal cancer can often lead to a complete cure. Today, there are over 1.4 million survivors of colorectal cancer in the U.S., and that success is largely due to awareness, screening and treatment programs, and educational initiatives such as Colorectal Cancer Awareness Month every March.

Colorectal cancer screening guidelines — age, high-risk populations and other considerations

Many factors make someone more susceptible to colorectal cancer and, therefore, increase the need and frequency of screening tests. High-risk groups include those who are older than 45, drink alcohol, smoke tobacco, have colorectal polyps or eat a lot of red or processed meats. In addition, someone who has a family history of colorectal cancer or has inflammatory bowel disease (ulcerative colitis or Crohn’s disease) falls into this high-risk population. All adults, even if not part of the high-risk population, should have a screening test at age 45.

Kathryn E. Hitchcock, MD, PhD, a UF Health radiation oncologist on the gastrointestinal oncology team, stresses the importance of colorectal cancer screenings.

“The chances of curing the cancer while it is very small or, better yet, while it is still a precancerous polyp, are thousands of times better than if we don’t find it until it is causing symptoms,” she said.

Colorectal cancer screening tests — the Gold Standard and noninvasive alternatives

There are several types of colorectal cancer screening options. Stool tests such as the fecal occult blood test, or gFOBT, the fecal immunochemical test, or FIT, and the stool DNA test, or sDNA, look for small amounts of bleeding caused by polyps or small cancers. Another type of testing, called a flexible sigmoidoscopy, uses a flexible scope to view the last one-third of the colon. Often, stool tests and the flexible sigmoidoscopies are used together. A screening test called a colonoscopy is used to view the entire colon. Dr. Hitchcock prefers colonoscopies because they give a more in-depth look at the colon. Other screening options, such as the flexible sigmoidoscopy or stool testing, may miss precancerous polyps and actual cancers.

The power of education to overcome misconceptions about colorectal cancer screening

Like other types of cancers, there are many misconceptions about colorectal cancer.

“Most cancers are accidents that happen in our cells, not something we inherit,” Dr. Hitchcock said. “People seem to focus very strongly on the family inheritance idea and don’t get screening done if there is no colorectal cancer among their relatives. That is a huge mistake.”

Taking the initiative to protect your health means being screened regularly, practicing healthy habits and eating a low-fat, high-fiber diet.

Although there is a higher risk for colorectal cancer for those who consume a high-fat, low-fiber diet, it is not necessary to follow an extreme diet to avoid cancer. Cutting out all sugar, red meats and processed meats is not necessary, Dr. Hitchcock said.

“People with no family history of cancer can get any cancer. People with perfect personal habits, excellent diets, good body weight, no smoking or drinking, and lots of exercise can also get any cancer,” Dr. Hitchcock said. “Good habits reduce our risk, but they don’t by any means eliminate it.”

Having seen the tragedies that follow a lack of cancer screenings, Dr. Hitchcock stressed again how important they are. “I cannot express to you the sadness of patients who sit in my office with me, admitting that if they had just gotten their colonoscopy on time, their lives would not be in terrible danger. Please don’t put yourself in that position,” she said.

This March, as we recognize Colorectal Cancer Awareness Month, talk to your doctor if you haven’t been screened for colorectal cancer.

FAQs

What are the symptoms of colorectal cancer?

The symptoms of colorectal cancer include:

• Abdominal pain or tenderness in the lower abdomen
• Blood in the stool
• Diarrhea, constipation or other change in bowel habits
• Narrow stools
• Unexplained weight loss

What are the screening tests for colorectal cancer?

• Stool test
  • There are various stool tests that check the stool for blood, which is caused by polyps and small cancers in the colon
• Flexible sigmoidoscopy
  • This test uses a small flexible scope to view the lower part of the colon
• Colonoscopy
  • This method is like the sigmoidoscopy, except the entire colon can be viewed. An alternative to the colonoscopy is a virtual colonoscopy, in which a CT scan is used to view the entirety of the colon

How do I know which test is right for me?

While the colonoscopy is often referred to as the gold standard of colorectal cancer screening tests, other tests are lower risk. The type of test that is right for the patient and when the patient should be tested is dependent on a careful assessment done by a physician.

For people at average risk, the ideal screening process is as follows:

• Colonoscopy every 10 years, starting at age 45
• gFOBT or FIT every year
• sDNA-FIT every 1-3 years
• Flexible sigmoidoscopy every 5 years or every 10 years, plus stool testing with FIT every year
• CT colonography (also known as virtual colonoscopy) every 5 years

People at higher risk need to be tested more frequently. This higher-risk group includes those who have:

• A family history of inherited colorectal cancer syndromes, such as familial adenomatous polyposis, also known as FAP, or hereditary nonpolyposis colorectal cancer, also known as HNPCC
• A family history of colorectal cancer or polyps, meaning a close relative (parent, sibling or child) developed these conditions before age 60
• A history of colorectal cancer or polyps
• A history of long-term chronic inflammatory bowel disease (ulcerative colitis or Crohn’s disease)

What are the benefits of early detection through colorectal cancer screening?

Curing colorectal cancer while it is a very small precancerous polyp is much easier than if the cancer is not found until it is causing symptoms. Early detection can be the difference between curable and incurable colorectal cancer. Something as simple as regular testing, even for those who are considered healthy, can save lives.