Background: Rural populations of the United States have not experienced a similar degree of decline in lung cancer mortality recently seen nationwide. Several investigations examining survival differences in rural lung cancer patients have been incongruent. We investigated the association of rural residence with survival outcomes and receipt of guidelines-concordant treatment in early-stage non-small cell lung cancer (NSCLC).
Methods: Retrospective study of National Cancer Data Base patients with NSCLC diagnosed from 2004 to 2015. Comparisons of survival outcomes and guidelines-concordant management with lobectomy or stereotactic body radiation therapy among rural and nonrural patients, classified according to the US Department of Agriculture's Rural-Urban Continuum Codes.
Results: We identified 840,566 patients; 18.7% resided in rural areas. Rurality was associated with greater proportions of males, white patients, and higher comorbidities. Larger proportions of rural stage I patients (53.4%) did not undergo guidelines-concordant management with lobectomy or stereotactic body radiation therapy relative to nonrural patients (50.1%, P<0.001). Although rural patients within each stage at diagnosis have a significant disparity in overall survival (OS), stage I NSCLC had the largest absolute difference (nonrural=61.4 mo, rural=50.3 mo, difference of 11.1 mo, P<0.0001). In multivariable Cox regression, rurality was independently associated with impaired survival in both all-stages (hazard ratio=1.08, P<0.001) and stage I NSCLC (hazard ratio=1.09, P<0.001).
Conclusions: Small differences exist in OS among all rural NSCLC patients, but rural patients with stage I NSCLC have a marked disadvantage in OS. Rurality is an independent risk factor for decreased survival in all-stages and stage I NSCLC.