Health/Colon Cancer and Polyps: What You Need to Know

CREDIT | Askmen.com

It would surprise many to learn that colon cancer is the third leading cause of death by cancer in American men. Over the past 10 years, more than 600,000 people have succumbed to this highly preventable and treatable cancer, and over 1.5 million have been diagnosed.

Colon cancer, sometimes referred to as colorectal cancer, usually starts as slow-growing precancerous polyps, a term used to describe bumps on the surface of the colon. Virtually all colon cancers begin with these growths. When found early, colon cancer is approximately 90% treatable.

Colon cancer risk factors

The lifetime risk for developing colon cancer is 1-in-18 and over 90% of these cases occur after the age 50. Increasing age, a family history of colon polyps, colon cancer or other early cancers can double or triple your risk for developing this disease. If any of these risk factors run in your family, you need to start the discussion about screening at age 40 or even earlier depending on when your family members were diagnosed.

Persons with ulcerative colitis, Crohn’s disease or a personal history of cancer are also at increased risk for colon cancer and need to tailor regular, more frequent colonoscopies.

Studies also indicate that diet and smoking may increase the risk of developing colon polyps and colon cancer.

While family history and other risk factors matter, not having risk factors does not eliminate your need for screenings.

What polyps tell us

As we age, about 1-in-4 of us develop polyps in our colon and about 10% of these polyps eventually turn from a benign growth into colon cancer. For the most part, these polyps take about 10 years to transform into colon cancer.

Polyps and early colon cancers often have no symptoms and can be detected only by screening exams.

How can colon cancer best be prevented?

There are several effective ways to reduce your colon cancer risk, but none more important than getting timely screenings and removing polyps before they become malignant.

Refraining from smoking, maintaining healthy weight and regular exercise, managing normal body levels of nutrients, especially vitamin D also appear to lower risk factors. Diets high in fiber are good for you, but have not been definitively shown to reduce colon cancer risk.

What are the symptoms of colon cancer?

Symptoms usually occur once tumors are advanced and causing obstruction or if the cancer has spread beyond the colon there may be rectal bleeding, anemia, abdominal pain, a change in bowel habits (constipation or diarrhea), unexplained weight loss, loss of appetite, recurrent fevers, unexplained nausea or vomiting, or fatigue.

However, colon cancer symptoms overlap greatly with other digestive conditions. Many times, especially in younger patients, symptoms are attributed to hemorrhoids or irritable bowel syndrome. Seven percent of colon cancers occur in people in their 40 and 3% under the age of 40. It’s important to take any of these symptoms seriously and request an evaluation.

If you experience any of these symptoms, until you are fully examined, no one -- not even a physician -- can definitively tell you the cause.

What are colon cancer screening options?

There are multiple screening options available that can often be confusing for the patient. For anyone at high risk for colon cancer, colonoscopy is the only recommended strategy.

Colonoscopy: Your physician will examine the inside of your colon and rectum using a long, lighted tube called a colonoscope, and removes any polyps found.

Virtual colonoscopy (CT scan colonoscopy): Images of the colon and rectum are taken using computerized tomography (CT). A computer puts the images together to create an animated, three-dimensional view. If abnormalities are detected, a colonoscopy is necessary.

Double contrast barium enema: The patient is given an enema with barium followed by air. The air pushes the barium against the walls of the colon in order to better visualize potential problems, such as polyps or tumors. If the test is abnormal, a colonoscopy is necessary.

Sigmoidoscopy: The doctor will examine the rectum and only the lower portion of the colon with a lighted tube. Where polyps are found, the doctor removes them.

Only a colonoscopy allows for both identification and removal of colon polyps throughout the entire colon and rectum. All other screening options require bowel prep, and if positive, will require a colonoscopy for confirmation and polyp removal.

For average-risk individuals, colonoscopy is recommended once every 10 years starting at age 50, and for African Americans, several societies recommend to start screening at age 45. Higher levels of risk require more frequent testing intervals and if polyps are found, follow-up surveillance with colonoscopy is recommended every five years.

Stool can be analyzed for evidence of bleeding or genetic abnormalities associated with colon cancer or large polyps. These tests are not designed to detect small- or medium-size polyps in their earliest stages. In order for these to effectively reduce colon cancer death rates, they must be repeated on an annual basis. When followed carefully, stool testing allows for intervention and detection of colon cancer at early stages leading to higher survival rates.

As you choose between the various types of testing, the best screening test is the one you will complete.