Lung stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer in the very elderly (≥80years old): Extremely safe and effective

Objective: Stereotactic body radiotherapy (SBRT) for early-stage non-small-cell lung cancer (NSCLC) is the standard of care in medically inoperable patients. In very elderly patients, previous studies have shown SBRT to offer excellent local control, though with higher toxicities than in younger populations. We report our institutional experience using SBRT in the definitive management of NSCLC in patients ≥80years old.

Materials and methods: Using an IRB-approved registry of 158 patients treated with definitive-intent lung SBRT for early-stage NSCLC at our institution between 2010 and 2016, 31 consecutively treated patients ≥80years of age were identified. CTCAEv4 scales were prospectively recorded during follow-ups and utilized for toxicity assessments. Kaplan-Meier estimates were utilized for survival analyses.

Results: For the 31 patients (with 34 lesions) included, median age was 83 (R: 80-93), median ECOG performance status was 2 (R: 0-3), and median follow-up was 15.8months (R: 3.1-48.3). Median PTV size was 24.0cm³ (R: 5.83-62.1cm³). Median prescription dose was 54Gy in 3 fractions (R: 50-60Gy in 3-8 fractions). Local control was 100% at 1year and 92.3% at 2years. Median survival was 29.1months. There were no grade 2-5 toxicities. Grade 1 toxicities included: fatigue in 5 patients (16.1%), asymptomatic (radiographic) pneumonitis in 12 (38.7%), and dyspnea in 2 (6.5%).

Conclusions: Lung SBRT with a BED of ≥100Gy10 for very elderly patients with NSCLC is extremely safe and effective, with inordinately low toxicity rates (zero grade 2-5 toxicities). With stringent dosimetric parameters and planning guidelines, patients ≥80years remain excellent candidates for full-dose SBRT.

Summary: SBRT for early-stage NSCLC is the accepted standard of care in medically inoperable patients, though in many very elderly patients, dose is either de-intensified or withheld for concern of toxicity in the setting of advanced age and competing risks. In this study of our very elderly (≥80years old) early-stage NSCLC patients, we highlight both the extremely high efficacy and tolerability (zero grade 2 or above toxicities) associated with definitive intent SBRT.