Definitive Radiotherapy for Inoperable Stage IIB Non–small-cell Lung Cancer: Patterns of Care and Comparative Effectiveness

• Published in: Clinical lung cancer 2020-05, Vol.21 (3), p.238-246
• Main Authors: Jacobs, Corbin D., Gao, Junheng, Wang, Xiaofei, Clarke, Jeffrey M., Tong, Betty, Ready, Neal E., Suneja, Gita, Kelsey, Chris R., Torok, Jordan A.
• Format: Article
• Language: English
• Subjects: Definitive radiation; Hypofractionation; Non-small cell lung cancer; Stereotactic body radiation therapy; Systemic therapy
• ISSN: 1525-7304; 1938-0690
• DOI: 10.1016/j.cllc.2019.10.005

The purpose of this study was to analyze practice patterns and perform comparative effectiveness of definitive radiotherapy techniques for inoperable stage IIB (American Joint Committee on Cancer eighth edition) non–small-cell lung cancer (NSCLC). Adults in the National Cancer Database diagnosed with T3N0M0 or T1-2N1M0 NCSLC between 2004 and 2015 who received definitive radiotherapy were identified. Cases were divided as stereotactic body radiotherapy (SBRT), hypofractionated radiotherapy (HFRT), or conventionally fractionated radiotherapy (CFRT) and stratified by systemic therapy (ST). Cox proportional hazards models evaluated the effect of covariates on overall survival (OS). Subgroup analysis by tumor size, chest wall invasion, multifocality, and ST use was performed with Kaplan-Meier estimates of OS. A total of 10,081 subjects met inclusion criteria: 4401 T3N0M0 (66.5% CFRT, 11.0% HFRT, and 22.5% SBRT) and 5680 T1-2N1M0 (92.5% CFRT and 7.5% HFRT). For T3N0M0 NSCLC, SBRT utilization increased from 3.7% in 2006% to 35.4% in 2015. Subjects treated with SBRT were more likely to have smaller tumors, multifocal tumors, or adenocarcinoma histology. SBRT resulted in similar or superior OS compared with CFRT for tumors > 5 cm, tumors invading the chest wall, or multifocal tumors. SBRT was significantly associated with improved OS on multivariate analysis (hazard ratio, 0.715; P < .001). For T1-2N1M0 NSCLC, patients treated with HFRT were significantly older and less likely to receive ST; nevertheless, there was no difference in OS between HFRT and CFRT on multivariate analysis. CFRT + ST is utilized most frequently to treat stage IIB NSCLC in the United States when surgery is not performed, though it is decreasing. SBRT utilization for T3N0M0 NSCLC is increasing and was associated with improved OS. There is a paucity of data to guide management of patients with inoperable stage IIB (American Joint Committee on Cancer eighth edition) non–small-cell lung cancer. Practice patterns and comparative effectiveness analyses were performed for 10,081 adults in the National Cancer Database diagnosed between 2004 and 2015 and treated with stereotactic body radiotherapy, hypofractionated radiotherapy, or conventionally fractionated radiotherapy. Stereotactic body radiotherapy utilization for T3N0M0 non–small-cell lung cancer is increasing rapidly and was associated with improved survival.