Radiotherapy Increases Adverse Cardiovascular Event Risk for Patients With Lung Cancer
A new retrospective study led by investigators from Brigham and Women’s Hospital and Dana-Farber Cancer Institute examined outcomes for patients after receiving treatment for locally advanced non–small cell lung cancer (NSCLC), finding that the average radiation dose delivered to the heart was associated with an increased risk of major adverse cardiovascular events and death. Among patients who did not have preexisting coronary heart disease, risk of having a major cardiovascular event after treatment exceeded the rates of people considered at high risk of such events. The findings were published by Atkins et al in The Journal of the American College of Cardiology.
“This is alarming data—to think that 1 in 10 of the patients I’m treating for this type of cancer will go on to have a heart attack or other major cardiac event,” said senior author Raymond Mak, MD, a thoracic radiation oncologist at Brigham and Dana-Farber, in a press release. “These cardiac events are happening earlier and more often than previously thought. More patients are living long enough to experience this risk of cardiac toxicity. We need to start paying attention to this and working together with cardiologists to help these patients.”
“When treating patients with lung cancer, it’s a balance of risks,” said lead author Katelyn Atkins, MD, PhD, a resident in the Harvard Radiation Oncology Residency Program. “But we need to start thinking about where there’s room for improvement in optimizing treatment for patients and room for improvement in terms of collaborating with primary care physicians and cardiologists.”
Study Methods and Findings
To conduct their study, researchers analyzed data and outcomes for 748 patients with NSCLC treated with thoracic radiotherapy at the Dana-Farber/Brigham and Women’s Cancer Center and Dana-Farber Cancer Institute/Brigham and Women’s Hospital at Milford Regional Medical Center. After treatment, a total of 77 patients (10.3%) experienced a major adverse cardiac event, including heart attack and heart failure. The team observed increasing risk of cardiac events with increased dosages of heart radiation exposure, especially among patients who did not have coronary heart disease before receiving radiotherapy.
Based on their findings, the authors recommend more stringent avoidance of high cardiac radiotherapy dose, and suggest considering a much lower cardiac radiation therapy dose limit for patients than national guidelines currently recommend (10 Gy vs 20 Gy).
“When possible, we should be thinking about ways to minimize cardiac radiation dose,” said Dr. Mak. “Recognizing that we may not always be able to do that, we’re now collaborating with our cardiology colleagues to explore early interventions to help mitigate the effects of cardiac injury from radiation therapy.”
Disclosure: For full disclosures of the study authors, visit onlinejacc.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
