Lonestar Gastroenterology

Our Services / Colonoscopy


You can hardly miss the barrage of TV commercials encouraging people to use Cologuard® to screen for colon cancer. The animated Cologuard character makes it sound like an easy way to learn if you’re at risk. But that’s not the whole story. The team at Lone Star Gastroenterology in Austin, Texas, believes it’s important to know your options. Cologuard can’t actually tell you if you have cancer, and it can’t prevent colon cancer. A colonoscopy can do both and treat the problem at the same time. To schedule an appointment, call the office today.

Colonoscopy Q & A

Why do I need a colonoscopy?

There are three reasons you need a colonoscopy to protect your health:

Reason 1: A colonoscopy screens for cancer by finding polyps.

A colonoscopy is the only way to screen for colon cancer by finding polyps that might be growing inside your colon.

Why is it so important to find polyps? Because that’s where colon cancer begins. Colon polyps originally start as noncancerous growths. But over the years, they can turn into cancer.

Reason 2: A colonoscopy prevents colon cancer.

During your colonoscopy, Lone Star Gastroenterology immediately removes any polyp that’s discovered in your colon. Eliminating polyps prevents cancer from ever developing. 

Reason 3: A colonoscopy can cure colon cancer.

Removing a polyp that has turned cancerous effectively treats the disease. As long as the cancer is contained in the polyp and hasn’t spread, your colonoscopy cures the disease.

How does Cologuard work?

Cologuard tests your stool for DNA markers and the presence of blood. Information from the DNA markers may signal the presence of precancerous and cancerous cells somewhere in your colon. Blood testing isn’t quite as informative because other colon conditions can bleed.

But Cologuard isn’t intended for everyone. The company emphasizes that you should have a colonoscopy if you’re at high risk for colon cancer.

You should also know that Cologuard test results can be wrong. A negative result doesn’t always confirm you’re free of cancer. At the same time, a positive test also doesn’t mean you have cancer for sure.

And here’s the kicker: If you have a positive Cologuard test, you still need to get a colonoscopy to determine if you actually have cancer and to treat the problem.

Did you know that most insurance companies will only pay for one colon cancer screening test? If you go with Cologuard first, they won’t cover the follow-up colonoscopy that’s essential for determining if you have colon cancer.

What are the disadvantages of Cologuard compared to a colonoscopy?

It’s true that Cologuard is noninvasive, and you do it at home. But that convenience may not be offset by the test’s disadvantages:

  • Cologuard only detects cancer after it develops
  • Cologuard misses 8% of colon cancers
  • Cologuard misses 60% of advanced polyps
  • Cologuard has a 13% false-positive rate
  • Cologuard must be repeated every three years

By comparison, most patients only need to repeat a colonoscopy every 10 years, and it’s the only colon cancer screening test that’s acceptable for patients who have symptoms.

A colonoscopy is the gold standard for detecting all cancerous and precancerous tumors. Simply put, colonoscopies are the only way to prevent colon cancer.

If you have any questions about colon cancer screening, you’d like to learn more about your risk for colon cancer, or you’re ready to schedule a colonoscopy, call Lone Star Gastroenterology today.