Radiation elevates cardiac risk in lung cancer patients: Study

Patients getting treated for locally advanced non-small cell lung cancer (NSCLC) are at a risk of heart attack and heart failure, a recent study has observed.

According to the study published in the 'Journal of the American College of Cardiology', 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 pre-existing coronary heart disease, risk of having a major cardiovascular event after treatment exceeded the rates of people considered at high risk of such events.

"This is alarming data -- to think that one 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 Raymond Mak, study's senior author.

"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," Mak added.

In many cases, a dose of radiation to the heart is the only way for oncologists to treat a patient with lung cancer.

"When treating patients with lung cancer, it's a balance of risks," said Katelyn Atkins, lead author of the study. "But we need to start thinking about where there's room for improvement in optimising treatment for patients and room for improvement in terms of collaborating with primary care physicians and cardiologists."

To conduct their study, Mak, Atkins, and colleagues analysed data and outcomes for 748 NSCLC patients treated with thoracic radiotherapy.

After treatment, a total of 77 patients (10.3 per cent) experienced a major adverse cardiac event, including heart attack and heart failure. The team observed an increased 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 recommended more stringent avoidance of high cardiac radiotherapy dose and suggested considering a much lower cardiac radiation therapy dose limit for patients than national guidelines currently recommend (10 Gy versus 20 Gy).