Does Administration of Antibiotics in Patients Undergoing Surgery for Colorectal Cancer Result in Less Complications and Better Prognosis?

Rationale: Infectious complications and especially anastomotic leakage severely impede the recuperation of patients following colorectal cancer surgery. When the normal gut barrier fails such as in anastomotic leakage, pathogenic microorganisms like Gram-negative bacteria enter the circulation and may cause severe sepsis which is associated with considerable mortality. Moreover, anastomotic leakage has a negative impact on colorectal cancer prognosis. Selective decontamination of the digestive tract (SDD) is a prophylaxis regimen that employs oral nonabsorbable antibiotics to eradicate pathogenic micro-organisms like Gram-negative bacteria. Objective: The primary objectives of this randomized clinical trial are to evaluate if perioperative SDD can reduce clinical anastomotic leakage rate and its septic consequences as well as other infectious complications. By reduction of septic complications long-term oncological outcome might simultaneously improve. Secondary objectives are a decline in reoperation rate, in-hospital mortality, readmission rate, duration of hospital stay and ICU admission, non-infectious complications, improvement of quality of life and reduction of costs. Study design: A randomised multicenter clinical trial comparing perioperative SDD in addition to standard antibiotic prophylaxis with standard antibiotic prophylaxis alone in patients with colorectal cancer who undergo elective surgical resection with curative intent. Study population: Patients 18 years or older are eligible for inclusion when they are diagnosed with colon or rectal cancer without signs of distant metastases. Patients may be scheduled for either laparoscopic or open resection with curative intent, including construction of an anastomosis (either with or without diverting stoma). Patients are not eligible for inclusion in case of concomitant metastases or acute obstruction. Intervention: Patients are randomly allocated for either perioperative SDD (intervention group) including standard antibiotic prophylaxis or standard treatment (including standard antibiotic prophylaxis alone) (control group). The solution containing SDD is orally taken 4 times daily, starting 3 days before surgery and continued until normal bowel passage or at least 3 days after surgery. Both groups receive a single preoperative intravenous dose of 1000 mg Cefazoline and 500 mg Metronidazole, which is the current standard antibiotic prophylaxis. Main study parameters/endpoints: The main study parameter is anastomotic leakage. The research hypothesis refers to an estimated decrease in anastomotic leakage rate in the SDD treated group (from 9% to 4%). As anastomotic leakage has been shown unfavourable forlong term oncological outcome, we presume an improvement in disease free survival, which serves as important secondary endpoint.