Variations in care for operable breast cancer and outcomes between rural and metropolitan centers in Australia

Abstract

e11517 Background: The causes of variation in breast cancer survival remain uncertain. Care provided to women with breast cancer may vary in relation to both the care setting and characteristics of the clinicians. Methods: To compare the outcomes of management of breast cancer treated in rural and metropolitan centers, a prospective audit of breast cancer in a region of Australia was undertaken. Over a nine-year observation period 2102 women with invasive breast cancer underwent potentially curative surgery. Treatments received, including systemic adjuvant therapy, were compared to contemporary guideline-based indicators. Breast cancer specific mortality was analyzed using Cox proportional hazards models. Results: Overall agreement of received treatment with the indicators was high. Women treated within rural centers were, however, much less likely to receive post operative radiotherapy after breast conserving surgery (86.4% vs. 97.0%; p<0.001). The overall recurrence rate, including distant metastases, for all women was 11.6%. Local or regional recurrence was more frequent in rural centers compared with metropolitan centers (4.1% versus 2.1%; p=0.05). Breast cancer mortality was increased in women with large tumors, high grade disease, and positive axillary lymph nodes. Non-compliance with treatment guidelines was associated with a trend towards increased breast cancer mortality (HR=1.55; p=0.056). After adjustment for these factors and patient age, undergoing surgery in rural centers was associated with increased breast cancer mortality (HR=1.84; p<0.001). Although women treated in rural centers were older, their cancer stage and tumour characteristics were similar to those of women treated in metropolitan centers. Non-cancer related mortality was elevated in women treated in rural centers compared with women travelling to a city for surgery (HR=2.08; p=0.005). Conclusions: Increased non-cancer related mortality in rural treated women suggests increased medical co-morbidity in this group, which may have influenced treatment choices and outcomes. Low rates of adjuvant radiotherapy were noted for women treated in rural centers. In addition, clinically significant differences in outcome, including breast cancer mortality, were observed. No significant financial relationships to disclose.