Original Medicare (Parts A & B): Colorectal Cancer Screenings (Colonoscopy and alternatives)

The overall lifetime risk of developing colorectal cancer is 1 in 23 for men and 1 in 25 for women, and risk increases with age. However, about 90% of colorectal-related deaths are thought to be preventable.  Therefore, everyone is encouraged to start regular colorectal cancer screenings at age 50 (the U.S. Preventive Services Task Force recently lowered this to age 45, though plan coverage starts at 50).  There are three groups of colorectal cancer screens—visual/structural (flexible sigmoidoscopy and colonoscopy), fecal-based (FIT, gFOBT, and mt-sDNA), and blood-based biomarkers.  While there are some differences between these tests to consider, the most important thing is to get screened, no matter which test is selected.

Colorectal cancer screenings are recommended for people who are at average risk of colorectal cancer, which is essentially everyone between the ages of 45–75 (after age 75, people should speak with their doctor and base screening on preferences, life expectancy, overall health, and prior screening history).  People are considered at average risk if they do NOT have a personal history of colorectal cancer or certain types of polyps, a family history of colorectal cancer, a personal history of inflammatory bowel disease (ulcerative colitis [UC] or Crohn’s), a confirmed or suspected hereditary colorectal cancer syndrome such as FAP or Lynch, or a personal history of radiation to the abdomen or pelvic area to treat prior cancer.

Available screenings

• Visual/Structural: flexible sigmoidoscopy (or barium enema as an alternative) every 48 months, colonoscopy every 10 years (or every 2 years if high risk), and newer CT colonography.

• Fecal-based: highly sensitive fecal immunochemical test (FIT) or highly sensitive guaiac-based fecal occult blood test (gFOBT) every 12 months, and multi-targeted stool DNA test every 36 months.

• Blood-based: blood-based biomarker test to screen for colorectal cancer every 3 years if between ages 45-85, show symptoms of colorectal disease (lower gastrointestinal pain, blood in stool, positive FIT or gFOBT), and at average risk for developing colorectal cancer.

The flexible sigmoidoscopy differs from the traditional colonoscopy in that it is a shorter test that only examines the rectum and sigmoid colon versus a thorough look at the whole of the large bowel, up to where it meets the small bowel (as with a colonoscopy).  Preparation for both tests is the same.