Rationale and Design of the CAN Study: an RCT of Survival After Propofol- or Sevoflurane-based Anesthesia for Cancer Surgery

Background: Based on animal data only, some clinicians have adopted propofol-based anesthesia for cancer surgery with the aim of increased survival.

Objective: Our objective is to verify or refute the hypothesis that survival increases after cancer surgery with propofol compared with sevoflurane for anesthesia maintenance. This aim deserves a large-scale randomized study. The primary hypothesis is an absolute increase of minimum 5%-units in 1- and 5-year survival with propofol- based anesthesia for breast or colorectal cancer after radical surgery, compared with sevoflurane-based anesthesia.

Method: Ethics and medical agency approvals were received and pre-study registrations at clinicaltrial.gov and EudraCT were made for our now ongoing prospective, randomized, open-label, multicenter study. A power analysis based on a retrospective study, including a safety margin for drop outs, resulted in a total requirement of 8,000 patients. The initial inclusion period constituted a feasibility phase with an emphasis on the functionality of the infrastructure at the contributing centers and at the monitoring organization, as well as on protocol adherence.

Conclusion: The infrastructure and organization work smoothly at the different contributing centers. Protocol adherence is good, and the monitors are satisfied. We expect this trial to be able to either verify or refute that propofol is better than sevoflurane for cancer surgery.