Colonoscopy

Preventing Colon Cancer Through Early Detection

A screening colonoscopy is a safe, effective procedure used to find and remove growths in the lining of the colon before they can develop into colorectal cancer. It’s both a diagnostic and preventive tool — unlike many other tests, a colonoscopy allows your surgeon to inspect the entire colon and remove suspicious lesions during the same procedure. Regular screening significantly reduces both the incidence of colorectal cancer and the risk of dying from it.

Most adults at average risk begin screening at age 45 and repeat it about every 10 years if no abnormalities are found.

Screening vs. Diagnostic Colonoscopy

Although the word “colonoscopy” is used in both cases, there is an important difference between screening and diagnostic procedures:

Screening Colonoscopy — Performed when there are no symptoms and you are at average risk. The goal is to find early signs of disease before symptoms develop.
Diagnostic Colonoscopy — Performed when symptoms are present (e.g., bleeding, change in bowel habits, unexplained pain) or when another screening test is positive and needs further evaluation.

In either case, the procedure itself looks the same, but the reason for doing it and, sometimes, insurance coverage may differ.

Colonoscopy vs. Cologuard (and Other At-Home Tests)

Cologuard and similar stool-based tests are non-invasive options that can help detect signs of early cancer in people reluctant to undergo colonoscopy. These tests look for blood and DNA changes in your stool.

However, there are important differences:

What Colonoscopy Offers

Direct visualization of the entire colon
Removal of polyps at the same time they are found
Prevents cancer by eliminating precancerous lesions
Typically done every 10 years for average-risk patients if no abnormalities are found

What Stool-Based Tests (e.g., Cologuard) Offer

Convenient at-home screening with no bowel prep or sedation
Detects some cancers and abnormalities
Must be repeated more frequently (e.g., every 3 years)
If positive, a colonoscopy is still required for diagnosis and polyp removal
Less effective at detecting smaller polyps compared with colonoscopy

Cologuard may be an option for individuals who decline colonoscopy, but it is not a replacement for colonoscopy in high-risk patients (those with symptoms, family history, inflammatory bowel disease, or prior polyps).

Polypectomy: Removing Polyps to Prevent Cancer

One of the key advantages of colonoscopy is the ability to perform a polypectomy — the removal of polyps during the same procedure. Polyps are small growths in the lining of the colon that can sometimes transform into cancer over time. Because colonoscopy allows for both detection and removal, it prevents many cancers before they start, which is why it remains the most effective screening tool available.

Once removed, polyps are sent to pathology to determine their type and whether follow-up should occur sooner than the standard 10-year interval.

What to Expect During Screening Colonoscopy

A screening colonoscopy typically includes:

Bowel preparation the day before to clear the colon
Mild sedation for comfort
A gentle, camera-assisted exam of the entire colon
Removal of any polyps or other suspicious tissue found

Most patients are comfortable and go home the same day, with minimal recovery time.

Understanding Diverticulosis

Many adults are found to have diverticulosis — small pouches that form in the colon wall — when they undergo a colonoscopy. This condition is common and often harmless. Most people with diverticulosis experience no symptoms and require no specific treatment. Other patients can experience diverticulitis over the course of their life. We can discuss if diverticulosis is present and whether any follow-up is appropriate.

When to Schedule Your Screening

If you are approaching age 45 or have questions about your risk, symptoms, or the right screening strategy for you, we’re happy to help guide you through your options and answer your questions.