Studies have shown an association between antibiotic use and an increased risk for colon cancer.
A Swedish population study from more than 40,000 colorectal cancer patients and 200,000 cancer-free control persons, found that moderate use of antibitotics increased the risk for proximal colon cancer by 9% and that very high antibiotic use increased the risk by 17%.
In contrast, the risk for rectal cancer was reduced by 4% with moderate use and 9% with very high use, but this association that was confined to women.
A history of antibiotic use among individuals younger than 50 appears to increase the risk of developing colon cancer (but not rectal cancer) by 49%.
Colon carcinogenesis with antibiotic exposure supports for the role of gut microbiota, providing justification for reducing antibiotics prescriptions in clinical practice
Antibiotics have a disruptive effect on the gut microbiome.
An increased risk for cancer in the proximal colon but not further along the alimentary tract relates to the high microbial impact in the proximal colon and a decreasing concentration of short-chain fatty acids along the colon.