Zhang J, Haines C, Watson AJM, et al. - Using the Clinical Practice Research Datalink from 1989 to 2012, researchers conducted a matched case-control study (incident CRC cases and up to 5 matched controls) to explore the connection between oral antibiotic use and colorectal cancer (CRC) risk. They identified 28,980 CRC cases and 137,077 controls. According to findings, penicillins, especially ampicillin/amoxicillin, raised the risk of colon cancer, while tetracyclines lowered rectal cancer risk. Significant interactions between antibiotic use and tumor location were observed. The antibiotic–cancer connection was found for antibiotic exposure occurring more than 10 years prior to diagnosis. Overall, the authors concluded that oral antibiotic use is correlated with enhanced colon cancer danger, but lower rectal cancer risk. This heterogeneity effect may suggest differences along the lower intestinal tract in the gut microbiota and carcinogenesis mechanisms.