Safe perioperative tamoxifen use in autologous breast free flap reconstruction: systematic review and meta-analysis

Background: Perioperative tamoxifen remains a valuable therapeutic modality for breast cancer patients. Studies in the existing literature have suggested a potential increased risk of thrombotic complications in autologous breast free flap reconstruction patients exposed to tamoxifen perioperatively. However, several recent publications have questioned the validity of these associations. Therefore, we aim to perform a systematic appraisal of the existing literature to determine if perioperative tamoxifen exposure increases the risk of flap complications in autologous breast-free flap reconstruction patients. Methods: A systematic literature search was performed using: PubMed, EMBASE, Cochrane Central, Web of Science, EBSCOHost, ClinicalTrials.gov, and TRIP databases from their inception up to April 2021. Articles analyzing the impact of perioperative tamoxifen in autologous breast free flap patients were included. The outcomes assessed were total flap loss, overall flap complications, thrombotic flap complications, which was defined as the sum of arterial and venous flap thrombi, and systemic venous thromboembolism (VTE). Pooled estimates and relative risk were calculated using a random effects model. Results: 9294 Articles were screened and 7 were selected for analysis, which included 3669 flaps in 2759 patients. Compared to patients who did not receive tamoxifen perioperatively, those who received tamoxifen did not have an increased risk of thrombotic flap complications (pooled RR 1.06; 95% CI 0.61–1.84), total flap loss (pooled RR 2.17; 95% CI 0.79–5.95), overall flap complications (pooled RR 1.04; 95% CI 0.76–1.41), or systemic VTE (pooled RR 1.93; 95% CI 0.72–5.13). The heterogeneity of the studies was not significant for any of the outcomes. Conclusions: The purpose of this study was to update the current understanding of the impact of perioperative tamoxifen on autologous breast free flap reconstruction outcomes. The existing literature supports that the perioperative continuation of tamoxifen in breast free flap patients is not associated with an increased risk of thrombotic flap complications, total flap loss, overall flap complications, or systemic VTE.