Analysis of a gut microbe could help distinguish between patients with precancerous adenomatous polyps and those with invasive colorectal cancer.
The method was more successful than assessing clinical risk factors and fecal occult blood testing, the American Association for Cancer Research reported. The findings were published in a recent edition of the journal Cancer Prevention Research.
"A person's gut microbiome is the collection of all the bacteria in their gut," said Patrick D. Schloss, PhD, associate professor in the Department of Microbiology and Immunology at the University of Michigan in Ann Arbor. "The number of bacteria in the gut is huge; it outnumbers the number of cells in our bodies 10 to one, and the diversity of the bacteria present is critical to our health. By sequencing the V4 region of the 16S rRNA gene we were able to identify the bacteria present in each individual's gut microbiome."
The team determined looking at the composition of the gut microbiome could effectively pinpoint which patients had invasive colorectal cancer. The team analyzed the stool samples of 90 individuals; 30 were healthy, 30 had precancerous adenomatous polyps, and 30 had invasive colorectal cancer. The team noticed a difference in the gut microbiome of all three groups.
The researchers used this information to identify the gut microbiome signatures for each group. They also factored in age and race, which in part determine one's clinical risk of precancerous adenomatous polyps; this boosted the accuracy of the test 4.5 fold.
"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."
"The study involved not just microbiologists but also researchers skilled in statistics, genomics, and epidemiology," continued Schloss. "Its success shows just how important interdisciplinary science is."
