['Patient and technical factors influencing postoperative infectious complications after elective colorectal resections for cancer are well described. Tumor related factors, however, have not been extensively evaluated.', 'This study aimed to measure the effect of tumor stage on postoperative surgical site and extra surgical site infections after elective colorectal cancer resection.', 'This was a retrospective matched-cohort analysis of prospectively gathered data.', 'The study was conducted in a tertiary referral center and a private hospital specializing in colorectal surgery.', 'Between 2004 and 2011, 740 consecutive patients underwent elective resection for colorectal cancer in 2 centers. Patients undergoing resection for advanced tumors (group A, ≥ stage IIB, n = 177) were matched to randomly selected patients with localized disease (group L, <stage IIB, n = 354). Matching variables were age, sex, American Society of Anesthesiologists score, malnutrition, and surgical approach.', 'We compared 30-day infectious complications rates between patients with advanced (group A) and localized (group L) tumors. Multivariable logistic regression analysis was performed to identify risk factors for infectious complications.', 'Group A had a higher overall rate of IC (44.6 vs 25.4 %, p < 0.001), with a higher risk of infectious complications at both the resection site (p < 0.001) and distant to the resection site (p = 0.015). Independent risk factors for infectious complications were advanced tumors (OR = 2.70; p < 0.001), obesity (OR = 1.89; p = 0.018), malnutrition (OR = 2.22; p = 0.008), and open rather than laparoscopic procedure (OR = 5.11; p < 0.001).'] Is advanced tumor stage an independent risk factor of postoperative infectious complications after colorectal surgery : arguments from a case-matched series?