Abstract P5-07-14: Chronic kidney disease in breast cancer treatment and survival

Background: Presence of chronic kidney disease (CKD Stages 3-5) prior to breast cancer diagnosis may increase the risk of mortality among women with invasive breast cancer. However, the evidence base is limited, and the magnitude of this mortality risk is unknown. Breast cancer therapy may also be altered by presence of CKD. We sought to understand the role of CKD in breast cancer survival, with particular attention to receipt of recommended treatment. Methods: All women diagnosed with invasive breast cancer from 1992-2016 in 18 SEER-Medicare sites (age 66 or older; n= 168701) were evaluated for breast cancer-specific mortality (BCSM) using multivariate Cox models, with estimation of hazard ratios (HR) and 95% confidence intervals (CI). All analyses were adjusted for age, race/ethnicity, diagnosis year, tumor characteristics, and socioeconomic factors, and also for diabetes, myocardial infarction, and congestive heart failure prior to diagnosis. Separate analyses were run according to receipt vs non-receipt of standard of care for breast cancer treatment (defined according to National Comprehensive Cancer Network (NCCN) guidelines. Results: Median follow-up was 63 months (26 months with CKD). Women with CKD were at increased risk of BCSM (CKD Stage 3: HR 1.2; 95% CI 1.0-1.5; CKD Stage 4 HR 1.7; 95% CI 1.3-2.2; CKD Stage 5/End Stage Renal Disease HR 1.5; 95% CI 1.1-2.1), compared to women without CKD. In analyses of any CKD, restricted to women who met NCCN guideline therapy recommendations, women had an elevated risk of BCSM regardless of whether they did (HR 1.6; 95% CI 1.1-2.1) or did not (HR 1.4; 95% CI 1.0-1.8) receive recommended chemotherapy, and whether they did (HR 1.6; 95% CI 1.1-2.3) or did not (HR 1.3; 95% CI 0.9-2.0) receive recommended radiotherapy. Discussion: Women with CKD have an increased risk of breast cancer mortality regardless of receipt of guideline-based treatment. CKD is underascertained in Medicare claims data, thus the reported results (likely underestimates) will be presented with sensitivity analyses. CKD may influence breast cancer outcomes due to associated systemic inflammation and comorbid conditions, as well as release of soluble mediators such as cytokines, chemokines, growth factors, and factors involved in remodeling of the extracellular matrix and epithelial-mesenchymal transition. As such factors involved in CKD progression also influence cancer, increased understanding may provide clues to ameliorate adverse outcomes in both disease entities. Citation Format: Deirdre A Hill, Christos Argyropoulos, Maria-Eleni Roumelioti, Mark Unruh. Chronic kidney disease in breast cancer treatment and survival [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-07-14.