Disparity in Treatment Receipt by Race and Treatment Guideline Revision Years for Stage 1A Non-Small Cell Lung Cancer Patients in the US.

ABSTRACT

INTRODUCTION: Treatment guideline revision introduced by the National Comprehensive Cancer Network (NCCN) is referred to by about 95% of the United States (US) oncologists in treatment decision-making for stage 1A non-small cell lung cancer. It is vital to account for this factor that affects the standard treatment receipt among stage 1A patients, with about a 75% survival rate if treated on time. The first choice for medically fit patients is lobectomy; however, over the decades since the initial guidelines were published, several medical advances have introduced trends in treatment receipt along with other sociodemographic factors that could help identify survival outcomes associated with treatment receipt. Establishing the role of treatment guideline revision years is important to determine a close to true causal relationship in racial treatment disparities. METHODS: US national cancer registry data for all US counties and historical Area Health Resource Files for the study period 1988-2015 were utilized. Logistic regression analysis was adjusted for clustering of standard errors at the state level and for time-invariant unobserved factors for the year of diagnosis and county. The time-invariant unobservable for each year of diagnosis and county specificity were accounted for by including their dummy variables in the regression model with standard errors clustered at the state level. RESULTS: Black patients, Medicaid beneficiaries, large fringe metropolitan residents, and those diagnosed post-2007 treatment revisions years are less likely to receive lobectomy, which is the standard treatment guideline for medically fit patients. CONCLUSION: The study concludes that there exists a difference in treatment type received among stage 1A NSCLC patients in the US by race, socioeconomic status, and treatment guideline revisions.