Colon cancer screening is testing done in people without symptoms to catch colorectal cancer early — or prevent it entirely by finding and removing polyps before they turn into cancer. Colorectal cancer is one of the most preventable cancers precisely because it usually develops slowly from polyps that screening can detect and remove. Regular screening is one of the most effective steps you can take to protect your long-term health.
When should you start colon cancer screening?
For people at average risk, screening should begin at age 45 and continue at regular intervals. You should talk with a gastroenterologist about starting earlier if you have a family history of colorectal cancer or polyps, a personal history of inflammatory bowel disease (Crohn’s disease or ulcerative colitis), or a known genetic syndrome such as Lynch syndrome. The right age and frequency depend on your personal risk.
Who is at higher risk for colorectal cancer?
Several factors raise the risk of colorectal cancer and may mean earlier or more frequent screening. These include a family or personal history of colorectal cancer or polyps, inflammatory bowel disease, certain inherited conditions, type 2 diabetes, obesity, smoking, heavy alcohol use, and a diet high in red or processed meat. If any of these apply to you, screening is especially important.
What are the colon cancer screening options?
There are several screening methods, and the best one depends on your risk and preferences:
- Colonoscopy — the gold standard, because it examines the entire colon and removes polyps in the same exam; typically repeated every 10 years for average-risk patients with normal results.
- Stool-based tests (FIT or multi-target stool DNA, e.g. Cologuard) — done at home more frequently; any positive result must be followed by a colonoscopy.
- Flexible sigmoidoscopy and CT colonography — additional options in select situations.
Our gastroenterologists help you choose the approach that fits your risk, and most patients at average or higher risk are best served by colonoscopy because it both screens and prevents in one step.
What do your colon cancer screening results mean?
Most colon cancer screenings come back clear. If your colonoscopy shows no polyps and you have no additional risk factors, you will usually not need another screening for ten years.
If we find colon polyps, we remove them during the same procedure and send them to pathology. Polyp removal is the reason screening works: the majority of colorectal cancers begin as a polyp, so taking it out interrupts the process before cancer has a chance to develop. Pathology tells us the polyp type and size, and those results set your next screening interval.
If a stool-based test such as FIT or Cologuard comes back positive, that is not a cancer diagnosis. It means blood or abnormal DNA was detected and the finding needs to be explained. The necessary next step is a diagnostic colonoscopy — repeating the stool test is not an adequate follow-up. We aim to schedule these promptly, because much of the benefit of a positive stool test is lost if the colonoscopy is delayed.
We go through every result with you directly, in plain language, and explain what it means for your follow-up schedule.
How often should colon cancer screening be repeated?
Your screening interval depends on what we find and on your personal risk, not on a single fixed rule.
For average-risk patients with a normal colonoscopy, the interval is ten years. If one or two small polyps were removed, it is typically five to ten years. Multiple polyps, larger polyps, or polyps with concerning features under the microscope usually shorten it to three years or less. Stool-based tests are not one-off screenings — FIT is repeated every year and Cologuard every three years, and skipping a cycle removes the protection.
Some patients need to screen more often whatever the results show. That includes anyone with a first-degree relative diagnosed with colorectal cancer, a personal history of inflammatory bowel disease such as Crohn’s disease or ulcerative colitis, or a known genetic syndrome such as Lynch syndrome.
If you have been screened elsewhere and are not sure when you are next due, bring the report to your visit and we will put you back on the correct schedule.
Do you offer direct-access screening?
Yes. Eligible, generally healthy patients can schedule a screening colonoscopy through our direct-access program without a preliminary office visit, making it easier to stay on top of screening. Contact us to see if you qualify.
Frequently asked questions