When’s the best time to get a colon cancer screening? And is it really necessary? (Spoiler alert: Yes!)

Johns Hopkins gastroenterologist Zachariah Foda, M.D, Ph.D., answers patients’ most common questions about colon cancer screening.

How do I know which colon cancer screening is right for me?

There’s an array of screening options available. These include:

• Colonoscopy : In this procedure, a doctor uses a long scope with a camera to check your colon for polyps.
• Various stool sample tests : Most of these test your stool for blood.
• Virtual colonoscopy : This is a CT scan of your colon that checks for polyps.

Each screening method has risks and benefits. Doctors recommend most healthy people start colon cancer screening at age 45. If nothing abnormal is found, the test you chose will determine when you need another screening.

One big benefit to a colonoscopy is that if any polyps are found, they can be removed at that time. No additional procedure is necessary. Your primary care doctor can discuss with you the colon cancer screening options available.

What is the prep for a colonoscopy?

The week before your colonoscopy, you’ll need to restrict your diet. The day before, you can only have liquids and you’ll drink a liquid that will help clear your bowels. This will mean multiple bathroom trips as your colon clears.

This prep process before your colonoscopy can be unpleasant. But it’s important. Following all prep instructions by your doctor will help ensure he or she can see your colon clearly, which then helps to spot anything abnormal.

Will a colonoscopy be covered by my insurance?

In general, yes. You should check with your insurance provider for specifics on which types of colon cancer screenings it covers and at what ages.

Are there any other ways I can prevent colon cancer?

Getting a colon cancer screening is the single most effective way to prevent colon cancer. In addition, studies have shown that diet and lifestyle can also lower your colon cancer risk. Here are some tips:

• Eat lots of fruits and vegetables.
• Eat yogurt regularly.
• Avoid or limit red meat.
• Exercise regularly and maintain a healthy body weight.
• Avoid excess alcohol.

My recent colonoscopy showed a few nodules that my doctor is testing. Should I be worried?

Not necessarily. Usually when colon cancer is present, there is a large lesion or a large mass in a lesion. If your colonoscopy shows a few nodules, the risk of the nodules being cancerous is very small.

Is colon cancer genetic?

In 20% of colon cancers, there is some hereditary link. If anyone in your family has been diagnosed with colon cancer (especially at a young age), you should tell your doctor.

He or she may want to monitor you more closely because of your family history or have you seen by a specialist. That could mean more regular colon cancer screenings to catch any signs of disease early.