Factors Associated With Treatment of Clinical Stage I Non-Small-cell Lung Cancer: A Population-based Analysis.

Background: The present study examined clinical stage I non-small-cell lung cancer (NSCLC) treatment in the population-based California Cancer Registry.

Patients And Methods: The characteristics associated with first clinical stage I NSCLC treatment (surgery, radiation, no local therapy) from 2003 to 2014 were identified using logistic regression. Survival was evaluated using Kaplan-Meier and Cox proportional hazard analyses.

Results: Surgery was used in most patients who met the inclusion criteria (14,545 of 19,893; 73.1%), although relatively similar numbers had undergone radiation (n = 2848; 14.3%) or not received therapy (n = 2500; 12.6%). Surgery use ranged from 68.5% to 77.2% patients annually. The percentage of patients with no therapy decreased from 18.1% (315 of 1737) in 2003 to 10.3% (176 of 1703) in 2014, and radiation use increased from 10.7% (185 of 1737) in 2003 to 21.2% (361 of 1703) in 2014. Patients who did not receive therapy were more likely to be older, not white, male, and unmarried, to have no insurance or public insurance other than Medicare, to live in a lower socioeconomic status neighborhood, to have been seen at a non-National Cancer Institute cancer center hospital or hospital serving lower socioeconomic status patients, and to have larger tumors. The 5-year all-cause survival after no therapy (12.7%) was significantly worse than that after surgery (64.9%) or radiation (21.5%; P < .0001).

Conclusion: In the present population-based analysis, surgery was the most common treatment for clinical stage I NSCLC but was not used for almost 27% of patients. Radiation use increased and the proportion of patients who did not receive any therapy decreased over time.