MALVERN, Pa. (WPVI) --When it comes to preventing colon cancer, the message is clear - if you're 50 or over, you should be screened.
In most cases, the recommendation is for a colonoscopy.
But if that isn't an option, or you want reassurance between screenings, there's now an at-home test.
Dr. Joseph Ferroni in Malvern, Chester County, has recommended Cologuard to some patients.
It's an at-home test approved by the FDA in late 2014.
It looks for the DNA and blood linked to colon cancer.
Last year, Dr. Ferroni tried it out himself, after the father of a close friend developed colon cancer.
Dr. Ferroni's colonoscopy 5 years earlier was all clear, so he was shocked when the Cologuard test came back positive, which meant he had to go in for another colonoscopy.
"I went and got a colonoscopy, and I had five polyps, two of which were precancerous," says D. Ferroni. "Now, I don't know what would have happened had I waited an extra 5 years to get to my 10-year mark."
The test is prescribed by a physician, but it goes directly to a patient's home, then back to the lab for processing. Results are sent to the doctor.
"We fax a request to the lab, they UPS a package to your home and that has everything you need to collect a stool sample," says Dr. Ferroni.
"There's no prep involved. You can have your normal diet the day of, the day before," he adds.
But he cautions that the test isn't for anyone at high-risk of colon cancer.
"Cologuard is not meant as a substitute for colonoscopy. Colonoscopy is still the gold standard," emphasizes Dr. Ferroni.
"But we have lots of folks, who for one reason or another can't or won't get a colonoscopy because of fear, because of medical conditions that would prevent them from having anesthesia, the fact that they may not have anyone to drive them back and forth," he adds.
In a clinical trial, it was found to be 92 percent effective at detecting colon cancers, and 69 percent effective at detecting high-risk pre-cancers.
But it is not perfect, with some chance of false positives and false negatives.
Medicare and many other insurance plans cover the test, and Dr. Ferroni says the test maker, Exact Sciences, has worked with some of his patients to get insurance coverage.
More information at CologuardTest.com.