CVD and cancer are the two most common causes of death in the United States. CVD and cancer intersect in both expected and surprising ways. For example, smoking as a shared risk factor now is unsurprising; however, recent cases of fulminant myocarditis seen after treatment with immune checkpoint inhibitors have been rather unexpected.
Cardio-oncology is emerging as a cross-disciplinary subspecialty focused on charting out and managing this complex bridging area between cancer and CVD. The CV care of the patient with cancer can occur at distinct stages along the cancer time line: at diagnosis, surrounding therapy, and during survivorship. It is cancer survivors who often pose the greatest challenge to cardiologists, perhaps in part due to the lack of comfort with onco-pharmacology and inadequate understanding of the horizon of CV toxicity. Whether it is the lung cancer survivor with a non-STEMI, the breast cancer survivor with subclinical cardiomyopathy or the childhood lymphoma survivor with mildly elevated BP, the survivor population demands and deserves our utmost attention.
Population studies of cancer survivors have revealed multiple gaps in CV clinical care. These generally revolve around three domains: primary prevention efforts, cardiotoxicity surveillance and management of CVD. The Childhood Cancer Survivor Study, a large longitudinal cohort of childhood and adolescent patients with cancer, has shown increased rates of modifiable CV risk factors, including hypertension, hyperlipidemia, obesity, diabetes, sedentary lifestyle and smoking, among cancer survivors compared with siblings. Interestingly, incident hypertension and anthracycline exposure increase multiplicatively the risk for development of HF in survivors of childhood cancer. This markedly increased risk raises the stakes for all primary prevention efforts such as routine health screening and smoking-cessation resources.
Besides prevention, the surveillance for and management of CVD in the survivor population is a challenging task. Patients with breast cancer treated with anthracyclines or the HER-2-targeted therapies — trastuzumab (Herceptin, Genentech) and pertuzumab (Perjeta, Genentech) — are at increased short-term and long-term risk for cardiomyopathy necessitating routine left ventricular ejection fraction assessment during treatment. Using a single-center tertiary care electronic medical record registry, we have uncovered surprisingly inadequate surveillance for cancer therapy-related cardiomyopathy. That same analysis, which we presented at the American College of Cardiology Scientific Session in March, revealed a large proportion of patients with documented cardiac dysfunction after cancer therapy who were not receiving guideline-directed medical therapies such as beta-blockers, ACE inhibitors and implantable cardioverter defibrillators.
The field of clinical oncology has made immense strides in the past 50 years, and while “cure” is an ever-elusive target, long-term survival has become a tangible outcome for many types of malignancy. With increased survival, the burden of CV risk becomes more evident. Cancer survivors pose a unique challenge to primary care providers and cardiologists, not only for clinical reasons but also due to implicit bias regarding competing risks. Multiple gaps exist in the routine CV care of the cancer survivor, especially around primary prevention efforts and surveillance for incident CVD. These gaps are ripe for innovative closure methods, perhaps leveraging the power of electronic health record systems to assimilate and distill data from multiple sources at a nationwide or even worldwide scale.
- Philips S, et al. Abstract 1105-069. Presented at: American College of Cardiology Scientific Session; March 10-12, 2018; Orlando, Fla.
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- Steven Philips, MD, PhD, is a cardiology fellow at UT Southwestern Medical Center. Vlad G. Zaha, MD, PhD, is an assistant professor in the division of cardiology, Advanced Imaging Research Center and Harold C. Simmons Comprehensive Cancer Center and medical director of the cardio-oncology clinic at UT Southwestern Medical Center. The authors can be reached by contacting Dr. Zaha at 5323 Harry Hines Blvd., UT Southwestern Medical Center, Dallas, TX 75390.
Disclosures: Philips and Zaha report no relevant financial disclosures.