Rural-Urban Variation in Time to Diagnosis and Treatment of Colorectal or Breast Cancer in Victoria, Australia

Abstract

Background: Rural-urban disparities in cancer outcomes are found in many countries, though these vary by cancer type. In Victoria, Australia, survival is poorer for rural patients with colorectal cancer, but not breast cancer. Delayed diagnosis and treatment may contribute to disparities, but previous studies have not compared the timeliness of rural and urban pathways to treatment of these common cancers. Aim: We investigated whether time to diagnosis and treatment differed for rural and urban patients with colorectal or breast cancer in Victoria, Australia. Methods: Population-based, cross-sectional surveys examining events and dates on the pathway to treatment completed by patients aged ≥ 40 and approached within six months of diagnosis, their general practitioner (GP) and specialist. Data were collected from 2013 to 2014 as part of the International Cancer Benchmarking Partnership, Module 4. Six intervals were explored: patient (symptom to presentation), primary care (presentation to referral), diagnostic (presentation/screening to diagnosis), treatment (diagnosis to treatment), health system (presentation to treatment) and total intervals (symptom/screening to treatment). Rural-urban differences were examined for each cancer using quantile regression (50th, 75th and 90th percentiles) models including age, gender, health insurance and socioeconomic status. Results: 433 colorectal (48% rural) and 489 breast (42% rural) patients, 621 GPs and 370 specialists completed surveys. Compared with urban patients, symptomatic colorectal cancer patients from rural areas had a significantly longer total interval at all percentiles: 50th (18 days longer, 95% confidence interval (CI): 9-27), 75th (53, 95% CI: 47-59) 90th (44, 95% CI: 40-48). These patients also had longer health system intervals, ranging 7-85 days longer. This appeared mostly due to longer diagnostic intervals (range: 6-54 days longer). Results were similar when including screen-detected cases. In contrast, breast cancer intervals were similar for rural and urban patients, except the patient interval, which was shorter for rural patients. Conclusion: Consistent with variation in survival, we found longer total and diagnostic intervals for rural compared with urban patients with colorectal cancer, but not breast cancer. The lack of rural-urban differences observed for breast cancer suggest that inequities in the timeliness of colorectal cancer pathways can be ameliorated, and may improve clinical outcomes. Indeed, based on previous research, delays observed in this study could result in stage progression and hence reduced survival. From our results, interventions targeting the time from presentation to colorectal cancer diagnosis in rural populations should be pursued. Countries seeking to understand cancer disparities in their local context may also consider using a pathways approach to identify possible targets for policy intervention.