Cardiotoxicity of Targeted Cancer Drugs: Concerns, “The Cart Before the Horse,” and Lessons from Trastuzumab

Purpose of Review Modern oncology is witnessing a renaissance of its pharmacologic armamentarium. Old generation drugs, such as anthracyclines and other cytotoxic or cytostatic drugs, were plagued with a lack of specificity and with the possible occurrence of untoward effects in the cardiovascular system and other healthy tissues. The old drugs are now combined with, or replaced by, new agents that are more specific in attacking some unique moieties and vital functions of cancer cells, causing less noxious effects in healthy tissues. Regrettably, however, the new “targeted” drugs still cause varying levels of cardiac or vascular toxicity. Here, we describe the case of trastuzumab, a monoclonal antibody that dramatically improved the life expectancy of women with Erbb2-overexpressing breast tumor, while also raising concerns about a possible incidence of cardiac dysfunction.