Colorectal Cancer: Symptoms, Screening and Prevention (video/podcast)

Scripps gastroenterologist explains preventive measures

Scripps gastroenterologist explains preventive measures

One of the most common cancers in the United States in also one of the most preventable. Colorectal cancer, which is cancer of the colon or rectum, affects about 150,000 people every year, but having a preventive screening exam just every ten years can greatly reduce the risk. 


In this video, San Diego Health host Susan Taylor talks with Walter Coyle, MD, a gastroenterologist at Scripps Clinic Anderson Medical Pavilion in La Jolla, about colorectal cancer symptoms and how to help prevent the disease.

Signs and symptoms of colorectal cancer

Colorectal cancer symptoms in the early stages can be subtle, such bleeding from the rectum, a change in bowel habits, abdominal pain and weight loss. Because these symptoms may be caused by other conditions besides cancer, people may not be concerned about them.


 “A lot of people will blame hemorrhoids for rectal bleeding,” says Dr. Coyle. “That’s the big trick, and that’s why if you’re not sure, you should see your primary care doctor. They may refer you to a gastroenterologist, who may need to do additional testing.”

Colorectal cancer risk factors

Unti recently, colon cancer has most often affected people over age 50. Men and African Americans have a higher risk of the disease, along with people who have a family history of the disease. Other risk factors for colorectal cancer include obesity, lack of exercise, a diet high in processed red meat and any inflammatory condition of the colon, such as inflammatory bowel syndrome.


However, Dr. Coyle says colon cancer is becoming much more prevalent among younger people.


“If you’re 30 or 35 years old and have bleeding, it could be a sign of early colon cancer,” says Dr. Coyle. “We’re not 100% certain why this is, but we think it’s something we’ve done in the environment, processed foods, antibiotics in our food source and our microbiome. But definitely people who are born after 1990 have a higher rate now of getting colon cancer early on.”

Colorectal cancer screening

Fortunately, colorectal cancer screening can detect cancer in its earliest stages, when it is easiest to treat. There are two basic screening procedures. One is a lab test that looks for signs of cancer in a stool sample.


The other, colonoscopy, is an outpatient procedure performed under sedation that inserts a scope into the colon to directly examine the lining of the colon and rectum for abnormal growths called polyps. The stool-based test is less invasive and less expensive, but if it finds something suspicious, you will still need to have a colonoscopy.


“During a colonoscopy, we can take pictures and biopsies, and if we see polyps, we remove them,” says Dr. Coyle. “The advantage of colonoscopy is we prevent colon cancer by taking polyps out and we can diagnose colon cancer right then and there.”


Dr. Coyle adds that about half of the polyps found during a colonoscopy are hyperplastic, meaning they would not develop into cancer. The other half are adenomas, which are precancerous and may or may not become cancerous.


Colon cancer usually develops slowly, so if you don’t have any polyps, screening is generally recommended every 10 years. If polyps are found, you may need to be screened every three, five or seven years based on the guidelines for the size and number of polyps removed. 


When should you start screening? The standard used to be 50, but because it is being seen in younger people, the recommendation has changed.


“If you have no family history of any GI diseases, it’s fine to wait to age 45,” Dr. Coyle says. “However, if you’re having pain, bleeding, family history, you should see your doctor sooner to address those issues now, so we can plan on when we should do our screening. If your mom had colon cancer at age 50, you should get your first colonoscopy 10 years earlier, or age 40, whichever is earlier.”

Colorectal cancer prevention

“This is a deadly but preventable disease,” says Dr. Coyle. “In addition to screening, you can help prevent colorectal cancer by maintaining a healthy weight, minimizing or avoiding red meat, especially processed meats, and exercising regularly.”


Talk to your doctor about other steps you can take to help prevent colorectal cancer.

Listen to the podcast on colorectal cancer prevention

Listen to the podcast on colorectal cancer prevention

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