UC Davis

Background

Multiple systemic treatments have been developed for stage IV non-small cell lung cancer (NSCLC), but their use and effect on outcomes at the population level are unknown. This study describes the utilization of first-line systemic treatments among stage IV NSCLC patients in California and compares survival among treatment groups.

Methods

Data on 17 254 patients diagnosed with stage IV NSCLC from 2012 to 2014 were obtained from the California Cancer Registry. Systemic treatments were classified into six groups. The Kaplan-Meier method and multivariable Cox proportional hazards models were used to compare survival between treatment groups.

Results

Fifty-one percent of patients were known to have received systemic treatment. For patients with nonsquamous histology, pemetrexed regimens were the most common treatment (14.8%) followed by tyrosine kinase inhibitors (11.9%) and platinum doublets (11.5%). Few patients received pemetrexed/bevacizumab combinations (4.5%), bevacizumab combinations (3.6%), or single agents (1.7%). There was statistically significantly better overall survival for those on pemetrexed regimens (hazard ratio [HR] = 0.86, 95% confidence interval [CI] = 0.80 to 0.92), bevacizumab regimens (HR = 0.73, 95% CI = 0.65 to 0.81), pemetrexed/bevacizumab regimens (HR = 0.68, 95% CI = 0.61 to 0.76), or tyrosine kinase inhibitors (HR = 0.62, 95% CI = 0.57 to 0.67) compared with platinum doublets. The odds of receiving most systemic treatments decreased with decreasing socioeconomic status. For patients with squamous histology, platinum doublets were predominant (33.7%) and were not found to have statistically significantly different overall survival from single agents.

Conclusions

These population-level findings indicate low utilization of systemic treatments, survival differences between treatment groups, and evident treatment disparities by socioeconomic status.