Trastuzumab in the treatment of metastatic breast cancer - Anticancer therapy versus cardiotoxicity

Trastuzumab, a monoclonal antibody against the HER:! receptor, was recently approved for the treatment of metastatic breast cancer. However, 28% of pa tients receiving both an anthracycline and trastuzumab developed heart fail ure. Although HER2 overexpression has been associated with the development of cancer, HER2 receptors seem to be cardioprotective because they mediate the activation of important cardiac survival pathways. Because the morbidit y and mortality of heart failure surpasses that of many cancers, prudent me dical practice mandates that physicians learn more about the mechanisms of trastuzumab-induced cardiotoxicity and develop algorithms for assessing ris k/benefit ratios before extending the use of this agent to patients with le ss invasive forms of breast cancer.