Breast cancer recurrence in patients receiving epidural and paravertebral anesthesia: a retrospective, case-control study.

PURPOSE Studies have suggested an association between the use of regional paravertebral or epidural anesthesia and a reduction in tumor recurrence following breast cancer surgery. To examine this relationship we performed a retrospective case-control study of patients undergoing breast cancer surgery receiving regional, regional and general, or general anesthesia. METHODS A retrospective chart review was performed of patients undergoing surgery for stage 0 to III breast cancer. Patients identified as receiving regional anesthesia were then matched for age, stage, estrogen receptor (ER) status, progesterone receptor status, and HER-2 expression with patients who received no regional anesthesia. Univariate (Pearson's χ2 test and odds ratio) and multivariate logistic analyses with backward stepwise regression were performed to determine factors associated with cancer recurrence. RESULTS Between 1998 and 2007, 816 women underwent surgery for stage 0-III breast cancer at our institution. Forty-five patients developed tumors. Univariate analysis showed the use of regional anesthesia trended towards reduced cancer recurrence, but it did not achieve statistical significance (p = 0.06). Higher recurrence rates were associated with ER positive status (p = 0.003) and higher tumor stage (p < 0.0001). Age and HER-2 status were not associated with increased cancer recurrence (both p > 0.11). Multivariate analysis confirmed ER status and stage as independently influential (p = 0.002 and p < 0.0001 respectively). CONCLUSION Although we found a trend towards reduced breast cancer recurrence with the use of regional anesthesia, univariate analysis did not reach statistical significance.