Lung cancer diagnostic and treatment intervals in the United States: a health care disparity?

INTRODUCTION: Lung cancer diagnostic and treatment delays have been described for several patient populations. However, few studies have analyzed these intervals among patients treated in contemporary health care systems in the United States. We therefore studied the timing of lung cancer diagnosis and treatment at a U.S. medical center providing care to a diverse patient population within two different hospital systems.
METHODS: We performed a retrospective analysis of consecutive patients diagnosed with non-small cell lung cancer stage I to III from 2000 to 2005 at public and private hospitals affiliated with the University of Texas Southwestern Medical Center. We recorded patient and disease characteristics; dates of initial radiograph suspicious for lung cancer, diagnosis, and treatment; and overall survival. Associations between these factors were assessed using univariate analysis, multivariate logistic regression, and Kaplan-Meier survival analysis.
RESULTS: A total of 482 patients met criteria for analysis. In univariate analyses, the image-treatment interval was significantly associated with race, age, income, insurance type, and hospital type (76 days for public versus 45 days for private; p < 0.0001). In multivariate analysis, only hospital type remained significantly associated with the image-treatment interval; patients in the private hospital setting were more likely to receive timely treatment (hazard ratio 1.85; 95% confidence interval, 1.37-2.50; p < 0.001). In univariate analysis, the image-treatment interval was not associated with disease stage (p = 0.27) or with survival (p = 0.42).
CONCLUSION: Intervals between suspicion, diagnosis, and treatment of lung cancer vary widely among patients. Health care system factors, such as hospital type, largely account for these discrepancies. In this study, these intervals do not appear to be associated with clinical outcomes.