Cancer and Cardiovascular Disease: The Complex Labyrinth

As our population ages, there has been an increase in the prevalence of cancer and heart disease [1]. Modern treatment strategies have led to improvement in the chances of surviving a diagnosis of cancer; however, these treatments can come at a cost [2]. Cardiotoxicity, a relatively new term in the medical literature, refers to the impact of cancer therapies on the heart and cardiovascular system [3, 4]. Cohort studies in pediatric cancer survivors have shown that cardiotoxicity is the second leading cause (after cancer recurrence) of morbidity and mortality in cancer survivors [5]. The potential negative impact of cancer drugs on the heart, however, is not new. In fact, we have known for years that cancer drugs, such as the anthracyclines, can cause severe and permanent heart damage including heart failure (HF). So why is there growing interest now? In 2005 trastuzumab in combination with chemotherapy was shown to significantly improve disease-free and overall survival in women with early stage HER2 positive breast cancer [6, 7]. While the dramatic improvements in clinical outcomes led to the widespread adoption of this treatment in clinical practice, it became readily apparent that women were experiencing higher rates of cardiac dysfunction than had been anticipated during clinical development—thus placing oncologists in a difficult situation—to treat or not to treat [8]! The last several years have seen the development and approval of a plethora of cancer drugs, many of which may negatively impact the heart and cardiovascular system. Tyrosine kinase inhibitors (e.g., sunitinib) can cause or exacerbate preexisting hypertension and BCR-ABL inhibitors (e.g., dasatinib) can cause Q-T prolongation. In the modern era of cancer therapy it is imperative that oncologists work closely with cardiologists in order to provide the best possible cancer care without compromising cardiac health [9]. This is particularly important for those patients with preexisting heart disease who then develop cancer and are exposed to potentially cardiotoxic cancer drugs. In this special issue we gain insight into the challenges that health care providers face when treating this unique population of patients. While our understanding of how modern cancer therapies impact the heart continues to evolve, many knowledge gaps persist. How do we identify cancer patients at high risk of car-diotoxicity? In this issue, M. Davis and colleagues highlight the importance of cardiovascular risk assessment in cancer patients prior to commencing therapy. In a cohort of prostate cancer patients, they identified a high prevalence …