About Cologuard and False Negative Results
Cologuard tests DNA from stool samples for the presence of abnormal cancerous or precancerous cells. Studies have shown that Cologuard detects 92 percent of colorectal cancers*. However, unfortunately, Cologuard detects only 42 percent of precancerous polyps. This means in over half of patients with polyps we miss the opportunity to catch precancer BEFORE it turns into cancer. Such a high false-negative rate for the detection of polyps disqualifies Cologuard as a screening test when the goal is to catch cancer at the earliest stage possible, ideally when pre-cancerous.
About Cologuard and False Positive Results
Also noteworthy is a relatively high number of false positives (13%) using Cologuard for cancer detection. What false positive means is that the patient may have a positive result, yet have neither colorectal cancer or a polyp. Obviously, a positive result for a test can leave the patient feeling extremely anxious and cause undue stress.
The upshot? Based on our decades of experience and expertise, we believe it’s best not to use the Cologuard test. Colon cancer is the #2 cause of cancer deaths and is fully preventable with a screening colonoscopy. A colonoscopy is one of the most important investments you can make in your health.
*Reference: Imperiale TF, Ransohoff DF, Itzkowitz SH, et al. Multitarget stool DNA testing for colorectal-cancer screening. N Engl J Med. 2014;370(14):1287-97.