March is Colorectal Cancer Awareness Month, which shines a national spotlight on this mostly preventable disease. Colorectal cancer is the second leading cause of cancer death in the United States for both genders. However, many cases of colorectal cancer can be prevented through certain measures, which include adopting healthy lifestyle habits and regular screenings. A colonoscopy is one such screening method where physicians can identify and remove pre-cancerous polyps (growths) in the lining of the colon and rectum before they turn into cancer.

Colorectal cancer is the third most commonly diagnosed form of cancer in men and women in the United States. In 2022, the American Cancer Society estimates more than 100,000 new cases of colon cancer and over 45,000 new rectal cancer cases will be diagnosed. The lifetime risk of developing colorectal cancer is roughly 4 to 5% for the average person. With cases on the rise among younger people under 50, it is especially important to spread the word about important screening information and what to expect when you undergo a colorectal cancer screening procedure.

What is a polyp?

A polyp is a pre-cancerous growth inside the colon or rectum that can eventually turn into cancer. However, if a polyp is removed before becoming cancer, this removes the risk in that location. If a polyp is seen during a colonoscopy and removed, it usually prevents cancer and prevents the need for surgery. 

Pre-cancerous polyp removal is how colonoscopy prevents death from colorectal cancer. This makes it the only screening test for cancer that is actually preventative at the same time, as opposed to tests like mammograms that can only diagnose but not treat lesions.

However, it is true that if cancer is found within a polyp or a mass is found that cannot be removed that contains cancer, you may need surgery to remove that portion of the colon or rectum. Even if you need surgery, colorectal cancer is usually still curable. This type of surgery is often performed using minimally invasively using laparoscopic or robotic approaches.

Screenings and Polyps

As most colorectal cancer develops from pre-cancerous polyps that start in the colon and rectum lining, there are screening methods used to detect and remove polyps before they become cancerous. Screening procedures, like a colonoscopy, have been proven in large population studies to prevent colorectal cancer development and allow already established colorectal cancers to be discovered at much earlier stages.

Alternatively, stool-based tests have been developed for those unable or unwilling to undergo a colonoscopy to detect the presence of pre-cancerous and cancerous lesions by sending a sample of stool off to be tested in a lab. If one of these tests comes back concerning a possible lesion, then a colonoscopy is usually the next step. Examples of these stool tests include FIT tests and Cologuard.

Do young people get colorectal cancer and are there any high-risk groups?

The fastest-growing demographic developing colorectal cancer is between the ages of 40 to 50. Around 11% of all colorectal cancer is diagnosed in people under the age of 50, which has led most societies to recommend starting to screen the average risk individual at age 45, not 50 as previously recommended.

Individuals with inflammatory bowel disease (ulcerative colitis and Crohn’s disease) are at an elevated risk for colorectal cancer development in their lifetime. People with a family history of colorectal cancer and a family history of pre-cancerous polyps also have a slightly increased chance of getting colorectal cancer and should start screening earlier than the general population, before age 45. Additionally, those who have a genetic predisposition to colorectal cancer, like Lynch syndrome and familial adenomatous polyposis (FAP), should start screenings much earlier than the general population, who are considered to be at average risk for the disease.

Why is screening essential for preventing colorectal cancer?

Most cases of early colorectal cancer usually have no symptoms. It is essential to screen before the onset of symptoms to prevent cancer by polyp removal or catch it early enough to cure it. Colorectal cancer is often curable if it is detected in its earliest stages. More than 90% of patients with early-stage cancer confined to the colon or rectum are alive five years after diagnosis. Even those that are not curable are usually treatable.

The colonoscopy procedure is usually not painful and the patient is sedated to minimize any discomfort. While the most feared part of the procedure is the bowel preparation beforehand, this is the most crucial part, as it allows the doctor to see the lining of the colon and rectum clearly and helps detect and remove even small polyps that can grow into cancer.

Most health insurance plans cover the cost of a screening test.

A major development in the field of public health and cancer prevention took place on May 18, 2021 when the U.S. Preventive Services Task Force provided updated recommendations regarding the age to begin screening for colorectal cancer. Adults should initiate screening for colorectal cancer at the age of 45, according to the new guidelines. This is a significant change by the task force, which previously recommended in its 2016 guidelines that screening for this cancer begin at the age of 50.

What else can I do to prevent colon cancer?

Researchers have drawn a connection between certain risk factors and an increased likelihood of cancer and polyp development. People may prevent many cases of colorectal cancer by modifying their diet and lifestyle. Regular exercise, eating a low-fat, high-fiber diet with lots of fruits and vegetables, and avoiding tobacco and smoking all lower your risk of developing colorectal cancer.

COVID-19 has shifted a great deal of focus away from preventative healthcare screenings. Fewer people are getting screened because of the pandemic. If you have fallen behind with your screenings or need to schedule your first exam, reach out to your primary care provider for guidance on how to safely and quickly get yourself back up to date. Screenings for colorectal cancer, such as a colonoscopy, have been found to be safe during the pandemic.

Editor's note: This article was originally published on March 4, 2020.