At-Home Colon Cancer Test Earns FDA Panel Recommendation
A new test has been approved by a panel of experts with the United States Food and Drug Administration (FDA). The test is an at-home colon cancer test that can screen for signs of the cancer with more than 90 percent accuracy.
Before new treatments, medications, or tests can be approved by the FDA, they must go through clinical trials. After the trials are over, a panel of experts with the FDA can review the particular item. The panel's decision to recommend or not recommend the product does not affect the FDA's final decision. The product in question is Exact Science Corporation's Cologuard test.
The Cologuard test takes stool samples and examines them for blood and abnormal DNA. Current colon tests, such as the fecal immunochemical testing (FIT), do not look for abnormal DNA in the stool. In some situations, small lesions and cancers will not bleed very much and might go unnoticed during a fecal test.
"By increasing the pick-up rate in this way," said Dr. Steven Itzkowitz reported by HealthDay. "We found that the new test had a 92 percent sensitivity for detection of colorectal cancer. That kind of result is really unprecedented for a noninvasive stool-based screening."
For this report, the researchers examined nearly 10,000 men and women who went to one of the 90 screening sites in the U.S. and the Canada. Each patient was screened for colon cancer in three ways, which were a standard colonoscopy, the FIT, and the new DNA at-home test where they mail their own stool sample to the laboratory. The researchers found that the colonoscopy screenings were able to detect cancer in 65 patients. Another 757 patients had advanced precancerous lesions.
When the researchers examined the effectiveness of the other two tests, they found that the Cologuard was able to identify colon cancer in 60 out of the 65 patients with an accuracy of 92 percent. The FIT test only detected 48 of the cancer cases with an accuracy of 74 percent. For precancerous lesions, the Cologuard was only able to detect 42 percent of the cases and the FIT only detected 24 percent of the cases.
"It's not a perfect test," Itzkowitz acknowledged. "But neither is a colonoscopy. Also, I don't think we're saying that this test should be done as a replacement for a colonoscopy, but rather as an adjunct. Certainly if a person who does this test comes out with a positive reading then they will need to do a colonoscopy afterwards to confirm it."
The test was recommended by all 10 members of the panel. In 2013, there were 143,000 new cases of colorectal cancer within the U.S. According to the U.S. National Cancer Institute, this type of cancer kills around 50,000 Americans per year. Doctors and researchers believe that if people screened for colon cancer earlier, more cases could be prevented.
The study was published in the New England Journal of Medicine.