Colorectal Screening: Choosing The Test That’s Best For You

Colorectal cancer screening, once prescribed for all adults beginning at age 50, should start earlier, says a panel of WCM gastroenterologists Andrea Betesh, MD, Lea Lowenfeld, MD, and Allison Yang, MD. The reason is to increase the odds of detecting—and beating—colorectal cancer, whose incidence is increasing in patients younger than 50.

Updated Guidelines for Colorectal Screening Age

“It used to be that everybody was recommended to get screened at 50. But we're now talking more about beginning at age 45 because we are starting to see more colorectal cancer in patients who are under 50,” said Dr. Betesh, Assistant Professor of Medicine in the Division of Gastroenterology. Both the American Cancer Society and the United States Preventative Services Task Force advocate starting screening at age 45, especially for African Americans, who face a greater risk than white for colorectal cancer, Dr. Betesh noted.

Colorectal cancer is the fourth most common type of cancer, most frequently diagnosed between ages of 65 and 74, with the median age being around 67. It affects one in 23 men and one in 25 women, and increasingly younger adults.

But regular screening can detect the disease early enough to treat it successfully, or even prevent it, said Dr. Lowenfeld, Assistant Professor of Surgery. “Screening colonoscopy detects most colon cancers and most rectal cancers before they begin producing symptoms,” Dr. Lowenfeld said.

Understanding Colonoscopies

Among the various colon cancer screening tests, the colonoscopy is the ‘gold standard.’ This procedure uses a long, flexible tube (colonoscope) with a tiny video camera at the tip to examine the inside of the colon for cancer, as well as small growths known as polyps. “Not only are we looking for colon cancer, but we're actually preventing colon cancer because we're removing polyps that can potentially grow into cancer over time,” Dr. Betesh said.

Preparing for a colonoscopy requires you to consume only clear liquids or Jell-O for the entire day before the procedure. After drinking the first half of the prep, you will start going to the bathroom. You finish drinking the prep later that night or early in the morning before your procedure, which is done under anesthesia. You will continue having some liquid stools after you've taken the prep with the goal of completely clearing out your colon so that your doctor can get a good look at it.

What is a Fecal Immunochemical Test

Another highly accurate colorectal cancer screening test is the FIT or fecal immunochemical test, which detects blood in the stool. “The benefit of the FIT is that you don't have to go through a colonoscopy,” Dr. Betesh said. “But if it's positive, then you need to follow it up with a colonoscopy. So, if you're really interested in getting a one-step test, the colonoscopy is the best choice,” she said.

How often you need to take either test may help you choose between them. A FIT or stool-based test typically is done yearly, while a colonoscopy, if it's normal and detects no polyps, is repeated every 10 years. “In most cases, when we find small polyps, we can remove them completely,” Dr. Lowenfeld said. “What kinds of polyps you have, their size and number will dictate how frequently we would recommend getting a colonoscopy in the future,” she added. Because polyps run in families, it is important to know if anyone in yours have had them, which will also determine whether you should have a colonoscopy.

“If colonoscopy does not sound like something you're willing to do, meeting with your doctor and getting a stool-based colon cancer screening test is absolutely something you should consider,” Dr. Betesh said. “Because colon cancer is so common and fatal for many people, the best screening test is the one that you're willing to do,” she added.

If you're not sure, then speak to your primary care doctor, gastroenterologist, or colorectal surgeon to help you decide which test is best for you.