Comparison of the Initial Loco-Regional Treatment Received for Early-Stage Breast Cancer between Elderly Women in Appalachia and a United States - Based Population: Good and Bad News.

Background: Breast conserving surgery (BCS) followed by radiation therapy (RT) (BCS+RT) is as effective for long-term survival of invasive early-stage breast cancer (ESBC) as mastectomy, and is the local treatment option selected by the majority of women with ESBC. Women of older age and vulnerable socio-demographic characteristics are at greater risk for receiving substandard (BCS only) and non-preferred treatments (mastectomy), such as populations of women from the Appalachian region of United States.

Methods: Using a retrospective cohort study design, we identified 26,106 patients from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked dataset and 811 patients from the West Virginia Cancer Registry (WVCR)-Medicare dataset age ≥ 66 diagnosed from 2003 to 2006 with stage I-II breast cancer. Multivariable logistic regression models estimated type of initial treatment received between WVCR-Medicare and SEER-Medicare patients, and the association with type of treatment.

Results: Overall, women in WV were 0.82 (95% CI 0.68-0.99) and 0.70 (95% CI 0.58-0.84) times less likely to have mastectomy or BCS only vs. BCS+RT, than those in SEER regions. Women in WV of increasing age, greater comorbidity, stage II disease, and non-white race were more likely to have mastectomy or BCS only vs. BCS+RT, whereas, those residing in areas of higher income, higher education, and metro status were less likely, than similarly characterized women from SEER regions.

Conclusions: Findings from this study suggest that the magnitude of disparities in breast cancer treatment between groups of women with more and less resources are even greater in the Appalachian region, than they are among US populations. Improving access to oncology treatment services, as well as, the implementation of patient navigation programs are needed to improve patterns of initial treatment for ESBC among at-risk populations.