It's a common test doctors have used to detect colon cancer for years, but new research now says the fecal occult test may actually be worthless.
Testing a stool for hidden blood is a common procedure, usually done as part of a yearly exam. If results reveal an irregularity, physicians have patients get a colonoscopy to see if there are actually any cancerous growths in the colon. If the test doesn't find anything, then a physician might not suggest a colonoscopy.
But according to a new study the test is wrong much more than it's right. "Ninety-five percent of the time, fecal occult blood testing failed to identify to identify people who had polyps and precancerous lesions in their colon," said Dr. Blair Lewis of Mt.Sinai School of Medicine.
Not only did the fecal test miss potential cancer 95 percent of the time, but a more extensive version of the test was also wrong at least 76 percent of the time.
With such a high rate of inaccuracy, Mount Sinai's Dr. Lewis says the test is nearly useless as a screening tool. "If you get a negative test that doesn't protect you, that doesn't give you any sense of reassurance that you don't have colon cancer or you don't have a colon polyp."
Experts have known about problems with the fecal test or a while. But it's still given to tens of thousands of patients. Why? Millions of people either can't afford, or just won't get, a colonoscopy.
"In practical terms, while everyone should have a colonoscopy, it's just not going to happen," said the Cleveland Clinic's Dr. James Church. He says, if used properly, the fecal test can be a helpful tool, but in the end everyone over the age of 50 should be getting a colonoscopy.
"Colorectal cancer is a very common disease, it's preventable, it's curable if caught early," Dr. Church said.
And for catching colon cancer early, the colonoscopy is the best tool we have.