A Harvard-led study examined stool samples from 354 women an average of 12 years after having precancerous colon polyps removed. Their gut microbiome profiles were distinctly different from matched controls — and strikingly similar to patterns seen in colorectal cancer patients. Key bacteria like Faecalibacterium prausnitzii were altered, along with 30 metabolites including sphingolipids. This suggests that people who've had adenomas removed carry a persistently altered gut environment that resembles the cancer-associated microbiome, even long after the polyps are gone. The findings raise the possibility that the gut microbiome is not just a bystander but an active participant in the progression from polyp to cancer.
