Reversible and irreversible cardiac dysfunction associated with trastuzumab in breast cancer

One of the newest agents used in the treatment of breast cancer is trastuzumab (Herceptin®), a new recombinant DNA-derived humanized monoclonal antibody against the proto-oncogene, HER-2/neu gene product. However, despite its proven clinical efficacy, serious adverse effects leading to trastuzumab-induced cardiomyopathy have been described in up to 27% of patients receiving combination therapy with anthracyclines [1]. There has been little published on the clinical syndrome of trastuzumab-induced cardiomyopathy. We describe three cases, of both reversible and irreversible cardiomyopathy, associated with the use of this novel and effective agent in HER-2 overexpressing breast cancer.