Using proton therapy to treat lung cancer patients may help reduce the risk of radiation-induced heart diseases, according to research to be presented October 25 at the American Society for Radiation Oncology (ASTRO) 2020 virtual meeting.
Lung cancer patients who receive traditional photon-based radiation therapy can experience cardiac problems afterward. But proton therapy, which can more precisely target tumors and spare nearby organs and healthy tissue, can reduce these side effects.
In the study to be presented at ASTRO 2020, researchers from Perelman School of Medicine at the University of Pennsylvania decided to investigate whether proton therapy indeed reduced cardiac problems downstream. They performed a retrospective trial that included more than 200 patients and was spearheaded by Dr. Timothy Kegelman, PhD, chief resident in Penn Medicine's department of radiation oncology.
Researchers found that proton therapy patients experienced fewer heart attacks: 1.1% versus 8.2% treated with photon radiation therapy during a median follow up of 29 months. They also found that ministrokes were significantly less common among patients who underwent proton therapy versus conventional photon-based radiation therapy.
Myocardial infarctions were also less common in the proton therapy group compared with the photon group: 2.3% versus 9%, but the difference was not statistically significant. Kegelman and colleagues found no difference in the number of cases of atrial fibrillation, coronary artery disease, heart failure, or stroke. However, they continue to compare the two approaches by analyzing the severity of the cardiac events and radiation dose to specific parts of the heart.
A large prospective, international, phase III clinical trial investigating the difference between proton therapy and photon therapy in lung cancer patients is underway. The trial is expected to complete patient accrual in 2022, according to a press release.
