THURSDAY, Aug. 7, 2014 (HealthDay News) -- Analyzing the composition of people's collection of gut bacteria -- also called the gut microbiome -- can help improve identification of those who are at risk for, or already have, colon cancer, according to a new study.

Researchers collected stool samples from 30 healthy people, 30 people with precancerous intestinal polyps and 30 people with advanced colon or rectal cancer in order to assess the composition of their gut microbiomes.

Each group had a different gut microbiome composition, according to the study published Aug. 7 in Cancer Prevention Research.

"If our results are confirmed in larger groups of people, adding gut microbiome analysis to other fecal tests may provide an improved, noninvasive way to screen for colorectal cancer," study author Patrick Schloss, associate professor in the department of microbiology and immunology at the University of Michigan, said in a journal news release.

Adding analysis of gut microbiomes to assessment of age and race -- known risk factors for precancerous polyps -- led to a 4.5-fold improved prediction of precancerous polyps, the investigators found. Adding analysis of gut microbiomes to assessment of age, race and body mass index -- known risk factors for invasive colorectal cancer -- led to more than a fivefold improved prediction of the disease.

The researchers also found that analysis of gut microbiomes was better than fecal occult blood testing (a type of stool sample test) at distinguishing people with precancerous polyps from those with invasive cancer.

Assessing body mass index (a measurement based on height and weight), fecal occult blood test results and gut microbiomes together was even more effective at distinguishing patients with precancerous polyps from those with invasive colon and rectal cancer, the study revealed.

"Our data show that gut microbiome analysis has the potential to be a new tool to noninvasively screen for colorectal cancer," Schloss said. "We don't think that this would ever replace other colorectal cancer screening approaches, rather we see it as complementary."