Tamoxifen use in microvascular breast reconstruction & its effect on microvascular complications: a systematic review & meta-analysis

Abstract

Background: Tamoxifen is a selective oestrogen receptor modulator that is used in the treatment of hormone receptor positive breast cancer. It has been shown to significantly reduce the risk of breast cancer recurrence and has been shown to improve breast cancer survival. It is however associated with an increased risk of thromboembolic events, with an increased risk in patients undergoing free flap breast reconstruction due to the prolonged period of immobility. As tamoxifen has implications for macrovascular thrombosis, this study aimed to assess if it has implications for microvascular thrombosis. Methods: A systematic review and meta-analysis was performed on all published data assessing the impact of tamoxifen on microvascular complications. Relative risk was calculated using the Mantel-Haenszel statistical methodology. Primary outcomes were arterial and venous complications and partial and total flap failure. Secondary outcomes were the incidence of deep vein thrombosis (DVT) and pulmonary embolism. Results: Five studies were identified for inclusion, comprising 2,528 patients. There was an increased rate of flap failure (2.8% vs. 1.55%) in those taking tamoxifen, however there was no statistically significant increase in risk (P=0.2). There was a slightly increased rate of post-operative pulmonary embolism in those taking tamoxifen (0.56% vs. 0.26%), but again this was not statistically significant (P=0.43). Conclusions: The use of tamoxifen in the perioperative period may have implications on the success of free flap breast reconstruction, as well as systemic implications for the patient. We recommend that tamoxifen be held for four weeks preoperatively until two weeks postoperatively to minimise the risk.