The Effects of Anesthetic Techniques on Time to Start of Adjuvant Chemotherapy, and Early- and Late-outcomes Following Surgery for Colorectal Cancer A Prospective, Multicenter, International, Observational, Pragmatic Study

Colorectal cancer (CRC) is the third most common cancer in the world with a high postoperative mortality (2 - 6%) as well as a low 5-year survival (40%). Despite advances in surgery and the use of minimally invasive laparoscopic surgery in recent years and adjuvant chemotherapy after surgery, long-term prognosis has only improved marginally. Epidural analgesia is commonly used as a part of the perioperative management of patients undergoing open, colorectal cancer surgery. Not only does it reduce pain and stress, epidurals have been shown to reduce perioperative inflammation and preserve immunological function, all of which may be beneficial in perioperative tumorigenesis. In several retrospective studies, anesthesia and choice of analgesia have shown to improve long-term survival, but no randomized studies have been published in the literature today. Similarly, the benefits of propofol anesthesia in comparison to inhalational anesthesia have recently been high-lighted in relation to cancer surgery, and many patients today request the use of epidurals, total intravenous anesthesia and loco-regional anesthetic technique during surgery, without clear evidence from prospective studies in the literature. Therefore, the question as to the real benefit of anesthesia technique in postoperative outcomes and tumor recurrence remain unanswered, and skepticism abounds amongst both surgeons and anesthesiologists. It is therefore important to study short- and long-term outcomes in patients undergoing CRC surgery, comparing epidural vs. no epidural or inhalational vs. total intravenous anesthesia. However, prospective, randomized studies are costly, require many patients, and the benefits of choice of anesthesia and analgesia on outcome remain uncertain from the current literature. There is a clear diffusion in practice across the world in the choice of anesthesia for patients undergoing CRC surgery, a lack of evidence in the literature and an absence of guidelines on best practice anesthesia care. We believe that by performing a large, prospective, observational, international, pragmatic study, with low costs, it will be possible to answer some of the important questions pertaining to the choice of anesthesia and analgesia. The clinical trials network at the European Society of Anesthesiology will play an important role in the success of this study.