Proton Beam Therapy in Elderly Patients With cT1-3N0M0 Non-small Cell Lung Cancer

To investigate the outcomes of elderly patients with cT1-3N0M0 non-small cell lung cancer (NSCLC) undergoing proton beam therapy (PBT).Between 2009 and 2019, 110 patients receiving hypofractionated PBT for cT1-3N0M0 NSCLC were retrospectively reviewed.The median follow-up was 36.5 months (range=4.9-131.0 months). In the elderly group (80 years or older), the 3-year overall survival and progression-free survival rates were 79.8% and 73.9%, respectively, and the corresponding rates in the younger group were 80.5% and 61.2%, respectively. Grade 3 radiation pneumonitis (RP) was observed in 4.4% patients in the young group, whereas no grade 3 RP was observed in the elderly group. Age was not a risk factor for symptomatic RP. There were no significant differences in the survival and adverse events between the elderly and younger groups.PBT may be a reasonable approach for treating lung cancer in elderly patients with T1-3N0M0 NSCLC.