Written or medically reviewed by a board-certified physician. See About.com's Medical Review Policy.
Updated November 19, 2014.
With respect to colorectal cancer, screening for early disease is tantamount to cure. If this cancer is detected early enough and still localized, the 5-year survival rate is a whopping 90%! Of note, colorectal cancer is treated with prophylactic polypectomy (removal of cancer-causing polyps) and possible adjuvant therapy (radiation and chemotherapy). Unfortunately, only 39% of cases are caught early on with 54% of Americans aged 50 years and older receiving any type of screening at all, and 42% receiving screening in the recommended time interval.
Nonadherence to screening among the average-risk American is likely attributable to the perceived discomfort, pain and embarrassment of such screening procedures. (After all, colonoscopy, the gold standard of screening, does require that a tube be inserted into your large intestine via your anus.) However, Cologuard is a new and noninvasive test that elicits no discomfort. It tests stool for the presence of blood and mutations which indicate cancer and its precursors.
Current Screening Tests for Colorectal Cancer
Written or medically reviewed by a board-certified physician. See About.com's Medical Review Policy.
Updated November 19, 2014.
Colorectal cancer is cancer that forms in the tissues of the colon (large intestine) or rectum (the final part of the colon that connects to the anus). It's the second most common cause of cancer death in the United States, claiming the lives of an estimated 50.000 American men and women each year.
Currently, the U.S. Preventive Services Task Force recommends that screening for colocrectal cancer start at age 50 and continue to age 75.
For men and women at average risk for colorectal cancer, colonoscopy every 10 years is the gold standard or best test when screening for the disease. (Colonoscopy is also curative because polyps that cause cancer can be removed during the procedure.) But if a person at average risk for colorectal cancer refuses colonoscopy, there are other options including:
- fecal immunochemical tests (FITs) which test for blood in the stool;
- flexible sigmoidoscopy which unlike colonoscopy examines only part of the colon;
- CT colonography (so-called "virtual colonoscopy);
- double-contrast barium enema (another radiographic diagnostic test).
What Is Cologuard?
Written or medically reviewed by a board-certified physician. See About.com's Medical Review Policy.
Updated November 19, 2014.
Cologuard is a stool DNA test that detects not only blood, which indicates colorectal cancer, but also DNA mutations and methylation biomarkers which are also associated with the disease. The test is noninvasive and requires one self-collected stool sample. Encouragingly, clinical trials showed that a one-time screen with Cologuard detected 92% of cancerous lesions in asymptomatic and average-risk individuals.
However, Cologuard has trouble detecting advanced cases of disease and also yields many false positives (false alarms).
Although the test's manufacturer recommends screening once every 3 years, screening guidelines with Cologuard have yet to be established. However, the Centers for Medicare and Medicaid Services, which has embraced the test, proposed coverage for this period in patients who are aged 50 to 85 years, show no symptoms of colorectal cancer (like blood in the stool) and are at average risk for developing the disease (including no personal history of precancerous polyps or family history of colorectal cancer).
Written or medically reviewed by a board-certified physician. See About.com's Medical Review Policy.
Updated November 19, 2014.
Cologuard represents another fantastic advance in our ability to diagnose and treat early stage colorectal cancer. Furthermore, the test is noninvasive which is great for people who squirm at the thought of colonoscopy. Nevertheless, despite being approved for use by the FDA and embraced by Medicare, the test has yet to be incorporated into current screening guidelines.
On final note, if you or someone you love is aged 50 years or above, it's imperative to receive screening for colorectal cancer.
Doing so saves lives! Don't wait--make an appointment to see your primary care physician today.
Written or medically reviewed by a board-certified physician. See About.com's Medical Review Policy.
Updated November 19, 2014.
Bhadkamkar N, Crane CH, Rodriguez-Bigas M, Kopetz S, Eng C. Chapter 21. Colorectal Cancer. In: Kantarjian HM, Wolff RA, Koller CA. eds. The MD Anderson Manual of Medical Oncology, 2e. New York, NY: McGraw-Hill; 2011. Accessed October 30, 2014.
Syngal S, Kastrinos F. Chapter 22. Colorectal Cancer Screening. In: Greenberger NJ, Blumberg RS, Burakoff R. eds. CURRENT Diagnosis & Treatment: Gastroenterology, Hepatology, & Endoscopy, 2e.
New York, NY: McGraw-Hill; 2012. Accessed October 29, 2014.
“A Stool DNA Test (Cologuard) for Colorectal Cancer Screening” from The Medical Letter published on October 14, 2014. Accessed from PubMed on 10/29/2014.