ASTRO 2020: Cardiac Events With Photon Versus Proton Radiotherapy for Lung Cancer
Posted: Thursday, November 5, 2020
In a study presented during the 2020 virtual edition of the American Society for Radiation Oncology (ASTRO) Annual Meeting (Abstract 1046), a team of investigators, led by Timothy P. Kegelman, MD, PhD, of Perelman School of Medicine at the University of Pennsylvania, Philadelphia, reported that treating patients with advanced non–small cell lung cancer (NSCLC) utilizing proton therapy may help to reduce the risk of radiation-induced heart diseases compared with photon therapy. Among more than 200 patients, the occurrence of mini-strokes was significantly less common with proton therapy versus conventional photon-based radiation therapy.
“While these findings are promising and add to growing evidence, more research and the results of the randomized trial will help us better determine and understand how treating with protons may reduce cardiac event risk,” Dr. Kegelman noted in an institutional press release.
A total of 98 patients received proton radiotherapy, and 104 received photon radiotherapy. The study found that 1.1% of patients with locally NSCLC treated with proton therapy experienced mini-strokes post treatment, after a median follow-up of 29 months, compared with 8.2% of patients treated with photon radiation therapy. Myocardial infarctions were also less common in the proton-therapy group compared with the photon-therapy group, although the difference was not found to be statistically significant (2.3% vs. 9%; P = .06). There appeared to be no difference in the number of cases of atrial fibrillation, coronary artery disease, heart failure, or stroke between the two types of radiotherapy. Of interest, overall survival at 3 years did not significantly differ between the groups (38.8% with proton therapy, 42.1% with photon therapy).
Disclosure: For full disclosures of the study authors, visit redjournal.org.