Introduction: Elucidating the relationship between Escherichia coli and outcomes after colorectal cancer surgery represents a crucial step towards improving our understanding of the complex interplay between the gut microbiota and colorectal cancer. By unraveling the role of E. coli in shaping postoperative outcomes, we may uncover novel avenues for personalized therapeutic interventions aimed at optimizing surgical management and enhancing the long-term prognosis of patients with colorectal cancer.

Material and methods: Stool samples were collected from all patients within 24 hours prior to surgery and subjected to microbiological analysis to detect the presence of Escherichia coli. Standard laboratory techniques, including culture-based methods and biochemical assays, were employed to identify and characterize E. coli isolates. Virulence factors, antimicrobial susceptibility patterns, and phylogenetic typing of E. coli strains were determined using molecular techniques such as polymerase chain reaction (PCR) and sequencing.

Results: Escherichia coli was identified in 40% of patients, with a median log10 colony-forming units per gram (CFU/g) of stool of 7. Among the E. coli isolates, 30% were found to possess virulence factors such as adhesins, toxins, and invasins. Antimicrobial susceptibility testing revealed 25% of E. coli isolates were resistant to ciprofloxacin, while 15% exhibited multidrug resistance

Conclusion: In conclusion, our cross-sectional study provides compelling evidence of the relationship between Escherichia coli colonization and adverse outcomes following colorectal cancer surgery. Patients colonized with E. coli were found to have a higher incidence of postoperative complications, SSI, anastomotic leaks, prolonged LOS, and increased 30-day mortality compared to non-colonized patients.