VAPOR-C trial: Volatile Anaesthesia and Perioperative Outcomes Related to Cancer

The VAPOR-C study concluded recruitment earlier than anticipated due to constraints within the strict federal funding timeline. We sincerely appreciate the dedication and contributions of the participating sites and collaborators in advancing this important research. While the dataset is smaller than originally planned, a comprehensive analysis is underway, and manuscript preparation has begun to ensure that valuable insights into feasibility and future research directions can still be derived.

Surgery is a primary treatment for more than 60 per cent of patients with cancer, with consequent exposure to anaesthesia. Alarmingly, retrospective clinical cohorts suggest that general anaesthesia with inhaled volatiles associates with reduced cancer-free and overall survival when compared with total intravenous anaesthesia (TIVA) with propofol.
Our preclinical mouse models confirmed these findings and also demonstrate that intravenous lidocaine reduces cancer progression. Factors may include the pro-inflammatory, pro-angiogenic, pro-survival, and immunosuppressive properties of volatile anaesthesia. Our survey of Australian practice found that more than 80 per cent of anaesthetists routinely use inhaled anaesthesia and less than 50 per cent of respondents felt that anaesthetic technique impacts cancer outcomes. This lack of clinical consensus on optimal anaesthesia for cancer surgery reflects the urgent need for a definitive randomised clinical trial. This definitive study will inform international anaesthesia guidelines and the findings rapidly translated as these drugs are generic, cheap, and available worldwide. We anticipate that this study will have a dramatic effect on individual wellbeing, population health, and health care costs.

Study design
VAPOR-C is a pragmatic, event-driven, randomised controlled trial, with a single blind 2x2 factorial design for sevoflurane/propofol and for intravenous lidocaine infusion / no lidocaine infusion and aims to study two primary hypotheses in patients undergoing colorectal or lung cancer surgery.

Primary endpoints
Propofol-TIVA and lidocaine increases disease-free survival compared with volatile anaesthesia.

Secondary endpoints
Will explore impact of anaesthesia on postoperative complications, quality of recovery, return to adjuvant therapies and incidence of chronic pain.

Sample size
An estimated total sample size of 3500 (875 per group) patients is required to achieve 850 events (failed disease-free survival within three years).

Study duration
Four years.

The Australian National Health and Medical Research Council and the Victorian Comprehensive Cancer Centre. 

ClinicalTrials.gov Identifier: NCT04316013

$A1000 per patient (+$A100 for MINS Sub-study participants) and a site start up payment of $A750.