By Saro H. Armenian, DO, MPH
Chair, ASCO Cardiac Dysfunction Expert Panel
Survival rates for many types of cancers have continued to improve over the past several decades, contributing to a growing number of long-term cancer survivors. In fact, it is estimated that by the year 2022, there will be approximately 18 million cancer survivors living in the United States. With longer survival, attention to the chronic and long-term adverse treatment effects has become increasingly important.
Cardiac dysfunction, presenting during or after completion of cancer treatment, is a well-recognized complication of cancer-directed treatment. The onset of either asymptomatic or symptomatic disease may also be responsible for interruption or discontinuation of cancer-directed therapy, potentially reducing the chance for long-term survival. In children (age 21 or younger at diagnosis) with cancer, there are well-established evidence-based guidelines to direct surveillance and prevention of cardiac dysfunction. The need for comparable screening guidelines in survivors of adult-onset cancers was paramount, so that proper interventions can be implemented to avert the risk of cardiac dysfunction during and following completion of therapy.
The ASCO Survivorship Guidelines Advisory Group recognized this guideline topic as a high priority for development, bringing together oncologists, cardiologists, family practitioners, radiation oncologists, guideline methodologists, patient advocates, exercise physiologists, epidemiologists, and advanced care practitioners to develop an evidence-based guideline which would help health care providers and patients alike. I was honored to co-lead the multidisciplinary Cardiac Dysfunction Expert Panel in using well-established standardized methodology to craft the guideline recommendations. We strongly considered the quality of the existing data and the strength of the evidence.
The result of these efforts, “Prevention and Monitoring of Cardiac Dysfunction in Survivors of Adult Cancers: ASCO Clinical Practice Guideline,” was published today. Read the complete guideline online and access supplemental tools and resources.
Importantly, this guideline is the only one of its kind to have been endorsed by both an oncology and a cardiology organization, having undergone an extensive review by both ASCO and the American Heart Association. This type of multidisciplinary collaboration is integral to the dissemination and implementation of these recommendations.
This guideline provides clear recommendations for monitoring and surveillance of patients at risk for cardiac dysfunction due to treatment-related exposures (e.g., anthracycline chemotherapy, certain targeted therapies, radiation therapy), as well as cardiovascular risk factors (e.g., hypertension, diabetes, smoking, physical inactivity) present during or after completion of cancer-directed therapy. The intensity of surveillance is largely dependent on the level of risk, as defined through careful review of the existing literature.
Key guideline recommendations include:
- Clinicians should avoid or minimize the use of potentially cardiotoxic therapies, if established alternatives exist.
- Prior to starting cardiotoxic therapy, clinicians should perform a comprehensive assessment, which includes medical history, physical exam, and screening for cardiovascular disease risk factors.
- Doctors should discuss the potential for heart problems with patients who are at increased risk for such complications prior to start of therapy.
- In patients who have an increased risk of developing heart problems, a tailored and detailed plan to monitor them throughout cancer treatment and beyond should be established.
We identified important gaps in knowledge pertaining to the cost-effectiveness of early screening, timing and type of intervention in asymptomatic patients, and optimal population-based surveillance strategies in long-term cancer survivors. Studies are needed to examine the cardiovascular pathogenic mechanisms associated with cancer treatment, as well as prevention of short- and long-term cardiovascular complications in cancer survivors. Ongoing collaboration between the oncology and cardiology communities is integral towards the development of such studies.
Dr. Armenian is a pediatric hematologist/oncologist, associate professor in the Departments of Pediatrics and Population Sciences, and director of the Division of Outcomes Research, Department of Population Sciences, at City of Hope.