A cancer geography paradox? Poorer cancer outcomes with longer travelling times to healthcare facilities despite prompter diagnosis and treatment: a data-linkage study

Background: Rurality and distance from cancer treatment centres have been shown to negatively impact cancer outcomes, but the mechanisms remain obscure. 
Method: We analysed the impact of travel time to key healthcare facilities and mainland/island residency on the cancer diagnostic pathway (treatment within 62 days of referral, and within 31 days of diagnosis) and one-year mortality using a data linkage study with 12 339 patients. 
Results: After controlling for important confounders, mainland patients with more than 60 minutes travelling time to their cancer treatment centre [OR 1.42; CI 1.25 to 1.61] and island dwellers [OR 1.32; CI 1.09 to 1.59] were more likely to commence cancer treatment within 62 days of GP referral and within 31 days of their cancer diagnosis compared to those living within 15 minutes. Island-dwellers patients were more likely to have their diagnosis and treatment started on the same or next day [OR 1.72; 95%CI 1.31 to 2.25]. Increased travelling time to a cancer treatment centre was associated with increased mortality to one year (30-59 minutes [HR 1.21; 95%CI 1.05 to 1.41], >60 minutes [HR 1.18; 95%CI 1.03 to 1.36], island-dweller [HR 1.17; 95%CI 0.97 to 1.41]. 
Conclusions: Island-dwelling and greater mainland travel burden was associated with more rapid cancer diagnosis and treatment following GP referral even after adjustment for advanced disease, however these patients also experienced a survival disadvantage compared to those living nearer. Cancer services may need to be better configured to suit the different needs of dispersed populations.