Impact of travel burden on clinical outcomes in lung cancer.

Purpose: Our study explores the influence of travel burden (measured as travel distance and travel time) on clinical outcomes in lung cancer patients.

Methods: A retrospective analysis of a single Bulgarian center was performed. A total of 9240 lung cancer patients were included in the study. Travel distance and travel time between patients' city of residence and the treating facility were calculated with an online tool to determine the shortest route for travel using the existing road network. The probability of survival was estimated using the Kaplan-Meier method, and differences in survival in each subgroup were evaluated with a log-rank test.

Results: About one third of all included patients were living in the same city as the treating facility (n = 2746, 29.7%). Overall survival in our patient population was significantly lower with increasing travel distance (p < 0.001, Mantel-Cox log rank) and travel time (p < 0.001, Mantel-Cox log rank). The 1-year OS rate according to travel distance was 27.1% in the same city group, 22.4% in < 50-km group, and 20.5% in ≥ 50-km group (p < 0.001). The corresponding values for the 5-year OS rate were 2.9%, 2.6%, and 1.4% (p < 0.001).

Conclusion: In this retrospective study, we discovered significant differences in the overall survival of patients with lung cancer depending on travel distance and travel time to the treating oncological facility. Despite having similar clinical and pathological characteristics (age, sex, stage at initial diagnosis, histologic subtype), the median overall survival was significantly lower in those subgroups of patients with a higher travel burden.