Colorectal cancer is a preventable disease that can turn deadly when not caught early. In fact, more than 50,000 people this year in the United States will die from colorectal cancer. Screenings — including colonoscopies, sigmoidoscopies and fecal immunochemical tests (FIT) — can significantly reduce the risk, but studies show many people who should be getting checked are not doing it.
In this episode of San Diego Health, Dr. Coyle joins host Susan Taylor to discuss colorectal cancer, its causes, symptoms, treatments, who should get checked and when.
Most colorectal cancers start as a polyp or growth on the lining of the colon or rectum. Not all polyps are cancerous. Adenomas are polyps that can change into cancer. Hyperplastic polyps are common, but in general are not precancerous.
During its early stages, colorectal cancer may have no symptoms. Symptoms that appear may include change of bowel habits, rectal bleeding, cramping or abdominal pain, weakness and fatigue and unintended weight loss, according to the American Cancer Society.
About 140,000 men and women will be diagnosed with colorectal cancer this year in the US, according to the American Cancer Society.
While still one of the leading causes of cancer deaths in the US, the survival rate for colorectal cancer is improving. There are more than 1 million colorectal cancer survivors in the US. This is due largely to more people at risk getting screened and removing any colorectal polyps that are found before they can develop into cancers.
“If you find it early through screening, the five-year survival rate is 90 percent,” Dr. Coyle says.
Unfortunately, the survival rate for colorectal cancer shrinks dramatically when the cancer is caught late and has spread.
“That’s why screening is so important,” according to Dr. Coyle. “Even if you have cancer, we can save your life.”
Individual risk factors, such as ethnicity, lifestyle and family history, usually determine when to start getting screened for colorectal cancer.
Some lifestyle factors include “smoking, being obese, not eating lots of fresh fruit and vegetables and a diet that's high on red meat, particularly processed red meat,” Dr. Coyle says.
Family history is significant. “It’s important to talk to your mom and dad and brothers and sisters and ask, ‘What did your colonoscopy show?’ If you have a family history of colon cancer you might be able to be screened sooner,” Dr. Coyle says.
Race and ethnicity are also factors. African-Americans have the highest colorectal cancer rates among all racial groups in the US, according to the American Cancer Society. People of Eastern European Jewish descent have one of the highest colorectal cancer risks of any ethnic group in the world.
Screenings for colorectal cancer can be divided into stool-based tests and visual exams, which include colonoscopy and sigmoidoscopy.
Stool-based tests include FIT, which analyzes a stool sample for signs of cancer. “It’s a one-time test. You can do it and you can mail it back to your doctor’s office,” Dr. Coyle says. “It’s very good at detecting colon cancer, but not as effective in detecting polyps.”
Dr. Coyle says the most effective screening is a colonoscopy. This is a visual exam that allows physicians to examine the entire colon using a camera attached to a thin, flexible tube called a colonoscope. If precancerous polyps are found, they often can be removed during the procedure. “A colonoscopy hardly misses any colon cancers,” Dr. Coyle says.
A sigmoidoscopy is similar to a colonoscopy but looks only at the last portion of the colon closest to the rectum.
Early this year, the American Cancer Society lowered the recommended age to begin colorectal cancer screening to 45. Previously, it was 50. The change was due to a rise in the rate of young adults being diagnosed with colorectal cancer.
Dr. Coyle laments that only 60 percent of the people who should be screened for colorectal cancer actually take the test.
“The problem is people still avoid it,” Dr. Coyle says. He urged people at risk to make time to get checked.
“People get their cholesterol checked. Women are good about getting their mammograms. I’d put this at the same level. It’s a cancer that kills people. It’s easy to prevent,” he says.
Dr. Coyle says “it’s a shame” that men who should get screened aren’t doing it at higher rates.
He says the short time it takes to take the FIT test or even the lengthier colonoscopy is worth it given the importance of early detection. He calls it a “life or death” difference.