Travel time to healthcare facilities and stage at diagnosis and breast cancer-specific mortality: A population-based cohort study from Northern Ireland.

BACKGROUND: Travel time has been associated with worse outcomes for several cancers. In breast cancer patients, we examined stage at diagnosis and mortality by travel time to General Practitioner (GP) practice and cancer treatment hospital. METHODS: Women newly diagnosed with breast cancer from 2011 to 2021 were identified using the Northern Ireland Cancer Registry. The travel times by car from home address to GP practice and to cancer treatment hospitals were determined. The primary outcome was time to breast cancer-specific mortality up to March 2023. Secondary outcomes included stage at diagnosis. Cox regression models calculated adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) for breast cancer-specific mortality by travel time. RESULTS: The final cohort included 13,629 breast cancer patients. Among women living greater than 15 min by car from their GP practice, compared with less than 5 min, there was no association with later stage (5% versus 6% stage 4; adjusted odds ratio = 0.83 95% CI 0.61, 1.12) or breast cancer-specific mortality (adjusted HR = 1.10 95% CI 0.93, 1.10). Also, breast cancer-specific mortality was similar in women living greater than 60 min by car, compared with less than 15 min, from the hospital of their surgery (adjusted HR = 1.04 95% CI 0.88, 1.23), radiotherapy (adjusted HR=1.21 95% CI 0.99, 1.48) and systemic anti-cancer therapy (adjusted HR = 0.94 95% CI 0.75, 1.16). CONCLUSIONS: In our population-based cohort of breast cancer patients, longer travel times were not associated with worse outcomes or later stage at diagnosis.