Antibiotic exposure and colon carcinogenesis: In-depth profiling of a 492-patient cohort, with a focus on antibiotic classifications and subtypes.

e15643 Background: To investigate whether the use of specific antibiotics is associated with an increased risk of colon cancer incidence. Methods: We conducted a retrospective cohort study comprising 492 patients diagnosed with colon cancer between 2012 and 2022, with no prior malignancies and a minimum 5-year follow-up period. We collected demographic data, medical histories, and records of antibiotic exposure, categorizing antibiotics systematically based on the Anatomical Therapeutic Chemical (ATC) classification system. Patient antibiotic histories, including drug names, dosages, durations, and therapeutic indications, were included. Antibiotics were classified as broad-spectrum, narrow-spectrum, or extended-course. We performed univariate and multivariate logistic regression models and used propensity score matching to control for potential confounding variables, such as age, gender, co-morbidities, and concurrent medications. Subgroup analyses were conducted to identify specific antibiotic classes associated with an increased risk of colon cancer. Results: The mean age of the cohort was 65.7 years (SD ± 8.3), with an equal gender distribution. Adenocarcinoma was the predominant histological subtype (429 cases, 87%), with rare subtypes accounting for the remaining cases. Common co-morbidities included hypertension (226 cases, 46%), diabetes mellitus (108 cases, 22%), and hyperlipidemia (88 cases, 18%). The most frequently prescribed antibiotics were fluoroquinolones (158 cases, 32%), followed by cephalosporins (108 cases, 22%), and macrolides (88 cases, 18%). Extended-course antibiotics were administered in 138 cases (28%). Preliminary analysis revealed a statistically significant correlation between the use of extended-course antibiotics and the risk of colon cancer (Odds Ratio = 1.89, 95% Confidence Interval: 1.32-2.71, p < 0.05). No substantial association was observed with broad-spectrum or narrow-spectrum antibiotics. Subgroup analysis identified specific agents within the extended-course antibiotics, such as fluoroquinolones and clindamycin, with an elevated risk profile. Conclusions: This study suggests a potential association between the use of extended-course antibiotics and the development of colon cancer. Further validation through larger-scale, prospective studies is strongly recommended to confirm these findings. Further in-depth mechanistic inquiries, particularly in cellular signaling pathways and microbial interactions within the gut microbiome, are warranted to elucidate the underlying biological mechanisms driving this association.