Objectives
The authors performed a systematic review and meta-analysis of randomized and nonrandomized trials on the efficacy of dexrazoxane in patients with breast cancer who were treated with anthracyclines with or without trastuzumab.

Background
Breast cancer treatment with anthracyclines and trastuzumab is associated with an increased risk of cardiotoxicity. Among the various strategies to reduce the risk of cardiotoxicity, dexrazoxane is an option for primary prevention, but it is seldom used in clinical practice.

Methods
Online databases were searched from January 1990 up to March 1, 2019, for clinical trials on the use of dexrazoxane for the prevention of cardiotoxicity in patients with breast cancer receiving anthracyclines with or without trastuzumab. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model meta-analysis.

Results
Seven randomized trials and 2 retrospective trials with a total of 2,177 patients were included. Dexrazoxane reduced the risk of clinical heart failure (RR: 0.19; 95% CI: 0.09 to 0.40; p < 0.001) and cardiac events (RR: 0.36; 95% CI: 0.27 to 0.49; p < 0.001) irrespective of previous exposure to anthracyclines. The rate of a partial or complete oncological response, overall survival, and progression-free survival were not affected by dexrazoxane.

Conclusions
Dexrazoxane reduced the risk of clinical heart failure and cardiac events in patients with breast cancer undergoing anthracycline chemotherapy with or without trastuzumab and did not significantly impact cancer outcomes. However, the quality of available evidence is low, and further randomized trials are warranted before the systematic implementation of this therapy in clinical practice.