The Impact of Immunotherapy Use in Stage IIIA (T1-2N2) Non-Small Cell Lung Cancer: A Nationwide Analysis

Background Multiple clinical trials have shown the benefit of immunotherapy (IO) for non-small cell lung cancer (NSCLC), including unresectable stage III disease. Our aim was to investigate the impact of IO use on treatment and outcomes of potentially resectable stage IIIA NSCLC in a broader nationwide patient cohort. Methods We queried the National Cancer Database (2004-2019) for patients with stage IIIA (T1-2N2) NSCLC. Treatment and survival were examined with descriptive statistics, logistic regression, Kaplan-Meier analysis, and cox-proportional hazards modeling. Results Overall, 5.5% (3777/68,335) of patients received IO. IO use was uncommon until 2017, but by 2019 was given to 40.1% (1544/2308) of stage IIIA patients. The increased use of IO after 2017 was associated with increased definitive chemoradiation treatment (54.2% [6800/12535] years 2017-2019 versus 46.9 % [26,251/55,914] from 2004-2016, p<0.001) and less use of surgery (18.1% [2,266/12535] years 2017-2019 versus 22.0% [12,300/55,914] from 2004-2016, p<0.001). IO treatment was associated with significantly better 5-year survival in the entire cohort (36.9% vs 23.4%, p<0.001), as well as the subsets of patients treated with chemoradiation (37.2% vs 22.7%, p<0.001) and surgery (48.6% vs 44.3%, p<0.001). Pneumonectomy use decreased with increased IO treatment (5.1% of surgical patients [116/2266] in years 2017-2019 versus 9.2% [1127/12,300] from 2004-2016,p<0.001). Conclusions Increased use of IO was associated with a change in treatment patterns as well as improved survival for stage IIIA(N2) NSCLC patients.