Ethnic disparities in the treatment of stage I non-small cell lung cancer

Rationale: Important variations exist in the treatment of non-small cell lung cancer. Because resection is the most effective treatment for patients with early disease, disparities in surgical rates can generate considerable differences in outcomes. Objective: We analyzed data from a national population-based registry to evaluate disparities in the treatment of Hispanic and white patients with stage I lung cancer and to assess the extent to which these inequalities explain survival differences. Methods: This study included 16,036 Hispanic and white patients with stage I lung cancer diagnosed between 1991 and 2000. Cases were identified from the Surveillance, Epidemiology, and End Results registry. Survival was compared among white and Hispanics using Kaplan-Meier curves. Stratified survival curves and Cox regression were used to evaluate whether inequalities in stage (IA vs. IB) and resection could explain survival differences. Results: Hispanics had worse overall and lung cancer-specific survival compared with whites (p = 0.04 and 0.008, respectively). Five-year lung cancer survival was 54% for Hispanics versus 62% for whites. Hispanics were more frequently diagnosed with stage IB disease (p = 0.0002) and less likely to undergo resection (p = 0.03). Among resected patients, survival was similar for the two groups, as it was among those who did not undergo unresection. After adjusting for surgery and stage, there was no difference in survival between groups. Conclusions: Hispanics with stage I lung cancer had worse survival as compared with whites. These disparities are largely explained by lower rates of resection and higher probability of diagnosis at stage IB. Future work must delineate why Hispanics are receiving less surgery.