Thermal ablation matches sublobar resection outcomes in older patients with early-stage non-small cell lung cancer

Abstract

Purpose: To compare survival outcomes of sublobar resection and thermal ablation for early-stage non-small cell lung cancer (NSCLC) in older patients.

Materials and methods: SEER-Medicare linked data for patients with a diagnosis of lung cancer from 2007-2009 were used. Patients ≥ 65 years old with stage IA or IB NSCLC who were treated with sublobar resection or thermal ablation were identified. Primary outcome was overall survival (OS), and secondary outcome was lung cancer-specific survival (LCSS). Demographic and clinical variables were compared. Unadjusted OS and LCSS curves were estimated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox model. OS and LCSS curves for propensity score matched groups were also compared.

Results: The final unmatched study population comprised 1,897 patients. Patients who underwent sublobar resection were significantly younger (P = .006) and significantly less likely to have a comorbidity index > 1 (P = .036), a diagnosis of chronic obstructive pulmonary disease (P = .017), or adjuvant radiation therapy (P < .0001) compared with patients treated with thermal ablation. Unadjusted survival curves of unmatched groups demonstrated significantly better OS (P = .028) and LCSS (P = .0006) in the resection group. Multivariate Cox model adjusting for demographic and clinical variables found no significant difference in OS between the treatment groups (P = .555); a difference in LCSS (hazard ratio = 1.185, P = .026) persisted. Survival curves for matched groups found no significant difference in OS (P = .695) or LCSS (P = .819) between treatment groups.

Conclusions: After controlling for selection bias, this study found no difference in OS between patients treated with sublobar resection and thermal ablation.

Keywords: COPD; HR; LCSS; NSCLC; OS; SEER; Surveillance, Epidemiology and End Results program; chronic obstructive pulmonary disease; hazard ratio; lung cancer–specific survival; non–small cell lung cancer; overall survival.