3263 - Radiotherapy Fractionation and Travel Burden in Prostate Cancer: A National Analysis of Access, Time Savings and Environmental Impact
Presenter(s)
M. El Sayed1, D. T. Marshall2, and S. L. Cooper3; 1Medical University of South Carolina, Charleston, SC, 2Medical University of South Carolina - Hollings Cancer Center, Charleston, SC, 3Department of Radiation Oncology, Medical University of South Carolina, Charleston, SC
Purpose/Objective(s): Hypofractionated radiotherapy regimens are endorsed for prostate cancer, yet their population-level impact on patient travel burden remains incompletely quantified. We evaluated the association between radiotherapy fractionation and travel burden, time savings, and environmental impact using a national cohort.
Materials/Methods: Men with non-metastatic prostate cancer treated with external beam radiotherapy were identified from the National Cancer Database. Fractionation was categorized as conventional fractionation, moderate hypofractionation, or ultra-hypofractionation (SBRT) as per National Comprehensive Cancer Network (NCCN) definitions. To minimize lodging misclassification, the primary analysis was restricted to patients traveling =40 miles to the treating facility. Travel Burden Index (TBI) was defined as 2 × straight-line distance × number of fractions. Log-transformed multivariable linear regression estimated adjusted differences in TBI controlling for age, PSA, clinical T stage, clinical N stage, Gleason grade group, androgen deprivation therapy (ADT), facility type, year of diagnosis, and distance. Percent change was calculated as (e^ß - 1) × 100. Time savings and tree-seedling equivalents were derived from miles saved relative to a 44-fraction reference. Sensitivity analysis was performed among patients traveling <30 miles.
Results: A total of 135,191 patients were included (conventional n=89,619; moderate n=29,254; SBRT n=16,318). In adjusted analyses, moderate hypofractionation was associated with a 33.6% reduction in TBI compared with conventional fractionation (ß=-0.41, 95% CI -0.54 to -0.29, p<0.001), and SBRT with a 90.1% reduction (ß=-2.32, 95% CI -2.80 to -1.84, p<0.001). These differences translated to median travel time savings of 5.7 hours (IQR 2.8–10.9) for moderate hypofractionation and 15.8 hours (IQR 7.6–29.2) for SBRT. At the population level, this corresponded to approximately 6,560 and 2,520 tree-seedling (10-year) equivalents per 1,000 patients, respectively. Findings were consistent in sensitivity analysis (<30 miles).
Conclusion: Shorter radiotherapy regimens are associated with substantial reductions in travel burden, time commitment, and estimated environmental impact in patients who would be clinically appropriate for a shorter duration regimen. Hypofractionation may meaningfully improve access while reducing logistical and environmental costs of prostate cancer care.