Colorectal cancer (CRC) is the fourth most common cause of cancer death worldwide, estimated to be responsible for 610,000 deaths in 20081. The number of CRC patients is concomitantly increasing due to a higher incidence, population growth, aging of the population and the recently established nationwide screening. Surgery remains the predominant curative treatment type for CRC, but has a major impact on the patient's wellbeing by demanding large amounts of metabolic reserves. This can lead to the development of frequently observed and severe postoperative complications. Anastomotic leakage (AL) is the most important complication after colorectal surgery and has an incidence of 8-15% in the Netherlands. AL is associated with high short-term mortality rates of up to 40%. Even though many attempts have been made to prevent this dreaded complication, none of these interventions have been successful so far. Despite proper patient selection, reduction of known preoperative risk factors and improved surgical techniques as well as introduction of 'fast track' protocol, AL incidence has not decreased in the past decade(s). AL is associated with a decreased disease-specific survival and an increased recurrence rate of CRC. The aim of this study is to investigate potential strategies to prevent AL, to be able to diagnose AL in time and therefore start treatment as early as possible in the process.