Cardiotoxicity is a serious adverse effect of anticancer drugs, impacting on quality of life and overall survival of cancer patients. According to the current standard for monitoring cardiac function, cardiotoxicity is usually detected only when a functional impairment has already occurred, precluding any chance of preventing its development. Over the last decade, however, a new approach, based on the use of cardiac biomarkers, has emerged, and has proven to be an effective alternative strategy for early detection of subclinical cardiac injury. In particular, the role of troponin I in identifying patients at risk of cardiotoxicity and of angiotensin-converting enzyme inhibitors in preventing left ventricular ejection fraction reduction and late cardiac events represent an effective tool for the prevention of this complication.