Does the type of anesthesia really affect the recurrence-free survival after breast cancer surgery?

BACKGROUND: Although previous studies have suggested that propofol inhibits cancer recurrence and metastasis, the association between anesthetic agents and the recurrence of breast cancer has not been clearly investigated. We compared total intravenous anesthesia and balanced anesthesia with volatile agents to investigate the differences in their effects on recurrence-free survival and overall survival after breast cancer surgery. MATERIALS AND METHODS: The electronic medical records of 2,729 patients who underwent breast cancer surgery between November 2005 and December 2010 were retrospectively reviewed to analyze the factors associated with recurrence-free survival after surgery. Cox proportional hazards models were used to identify the risk factors for cancer recurrence and overall mortality after breast cancer surgery. RESULTS: Data from 2,645 patients were finally analyzed. The recurrence-free survival rate in this study was 91.2%. Tumor-node-metastasis staging exhibited the strongest association with breast cancer recurrence. However, we were unable to identify significant differences between the preventive effects of total intravenous anesthesia and those of volatile agents on postoperative breast cancer recurrence using Cox regression analyses and propensity score matching. Furthermore, the survival probability with regard to postoperative recurrence and mortality showed no significant differences among anesthetic agents. CONCLUSIONS: Our findings suggest that the effects of total intravenous anesthesia are comparable with those of volatile agents with regard to postoperative recurrence-free survival and overall survival in patients with breast cancer.