Use of Surgery and Stereotactic Body Radiotherapy (SBRT) In Very Elderly Patients with Early Stage Non-Small Cell Lung Cancer (NSCLC): A National Cancer Database (NCDB) Analysis

Abstract

SBRT treatment for very elderly (>80 years) patients with early stage NSCLC has been reported to be well tolerated with good short-term efficacy. Using a large hospital-based registry, we report a comparison of patterns of practice, outcomes, and prognostic factors for very elderly patients undergoing any treatment for early-stage NSCLC. The NCDB was queried for patients with clinical Stage I-IIA NSCLC with age ≥ 80 years diagnosed from 2004-2015 treated with surgery or SBRT alone. Patients were excluded if they received chemotherapy /immunotherapy or non-standard SBRT doses (i.e., > 5 fractions of RT, <30 Gy or >70 Gy total dose). Survival analyses were performed with propensity-matching, Kaplan-Meier estimates, Cox proportional hazards regression, and log-rank testing. 26039 patients met search criteria, median age 83 (80-90) years. 17141 (65.8%) patients underwent surgery, and 8898 (34.2%) underwent SBRT. Median follow up was 31 months. Median survival was 52 months for surgery and 35 months for SBRT. Of patients receiving SBRT, 2044 (23%) had a contraindication to primary surgery due to patient risk factors. 83% of patients were treated at comprehensive or academic/research cancer facilities. Age, clinical stage, tumor size, surgery type, CDCC score, BED, bronchial involvement, and type of treatment facility were predictive of median survival. BED > 154 Gy was associated with greater median survival (p<0.01). Lobectomy was associated with greater median survival vs sub-lobar resection or pneumonectomy (p<0.0001). Treatment at a community cancer program was associated with lower median survival. For Stage I tumors, surgery was associated with better median survival (56 months vs. 35 months, p < 0.0001), but for Stage IIA patients, both modalities had similar median survival (30 months vs 29 months, p = 0.04). Surgery remains the predominant treatment modality for early stage NSCLC in this very elderly patient population, and is associated with good outcomes for patients with Stage I tumors. For elderly patients who are poor surgical candidates due to medical co-morbidities SBRT is associated with reasonable median survival.