Stool Test Effective for Detecting Colon Cancer

Tests for blood in the stool can consistently detect colon cancer when used on an annual basis, and they are effective even in the second, third and fourth years of screening, a new study says.

The researchers said these findings suggest that the stool test could be a reasonable screening alternative to colonoscopy – currently considered the gold standard for colon cancer screening.

Known as fecal immunochemical tests, experts examine stool samples for microscopic amounts of blood shed by colon tumors, explained study co-author Dr. Douglas Corley, a research scientist with Kaiser Permanente in Oakland, Calif.

Doctors have been concerned that fecal blood tests might become less effective over time, hampering their usefulness as a screening tool, he said.

Researchers tracked annual fecal blood tests performed on nearly 325,000 Kaiser Permanente patients in California during a four-year period.

The first year of screening with fecal blood tests detected colon cancer in 84.5% of participants who were diagnosed with the disease, the study reported.

“We found that the sensitivity for cancer was somewhat higher in the first year, and that’s not surprising,” Corley said. “The first year you screen someone, for breast cancer or for anything, you’re going to find cancers that have been there for a while that may be larger or are easier to detect.”

However, the effectiveness of the fecal blood test varied between 73% and 78% in years two through four. That means the test remained capable of picking up new tumors as they grew to a detectible size, the researchers said.



The findings were published Jan. 25 in the Annuls of Internal Medicine.

These new results show that an annual blood fecal test could be just as effective as colonoscopy in screening for colon cancer, the researchers concluded.

Colonoscopy is an invasive procedure in which a tiny camera is run up into a person’s colon, Corley said. The procedure requires sedation, and the patient must take powerful laxatives the day before to “prep” their bowels for examination.

A fecal blood test is less intrusive and unpleasant. Plus, a sample can be gathered at home and dropped off for testing, experts noted. Based on these results, colon cancer screening programs should offer both fecal blood tests and colonoscopy. “You end up getting more people screened, because it allows people to select what works the best for them,” Corley said.

My Take:
This is a great option in lieu of traditional colonoscopy. The American Cancer Society now recommends yearly screening with a fecal stool test. However, they have not endorsed this testing in lieu of a colonoscopy every 10 years, but in addition. As a result, the test has not yet become as popular as it should.

Dr. Corley goes on to state that cost in not a consideration, as the Affordable Care Act requires that insurance companies pay for the full cost of colon cancer screening. Unfortunately, the public ultimately bears that cost in the form of insurance premiums. The fecal blood test is reimbursed at $500 per test, while the colonoscopy is $6,500.

The Bottom Line:
Please request your PCP (primary care physician) order this test as an integral part of your yearly physical. Consider it a viable option to replace colonoscopy.

January 25, 2016 National Institutes of Health