M. K. Wright1, A. Soran1,2, M. Zamanian1, C. Thomas2, G. M. Ahrendt1,2, M. Bonaventura1,2, E. J. Diego1,2, R. R. Johnson1,2, P. F. McAuliffe1,2, K. P. McGuire1,2 1University Of Pittsburg,School Of Medicine,Pittsburgh, PA, USA 2Magee Women’s Hospital Of UPMC,Surgical Oncology,Pittsburgh, PA, USA
Introduction:
Breast density is a well-established risk factor for the development of breast cancer. Some studies suggest that breast density is associated with a tumorigenic microenvironment within the breast, leading to more cancers and higher stage at presentation. We hypothesize that premenopausal women with dense breasts will present with breast cancer at a higher stage and will have worse long-term outcomes compared to their non-dense breasted counterparts.
Methods:
We performed a retrospective study of a prospectively collected database identifying premenopausal women with breast cancer who presented to a single institution between 2006 and 2010. Premenopausal status was defined as age less than 50 years or no menstrual period for at least one year. Patient and tumor characteristics were collected, as well as long-term outcomes. Patients were stratified into two categories of breast density: ‘non-dense’, defined as fatty replaced or scattered fibroglandular densities (BIRADS Density Categories 1 & 2, respectively) and ‘dense’, defined as heterogeneously dense or homogeneously dense (BIRADS Density Categories 3 & 4, respectively). The two breast density groups were compared for differences in presentation and outcomes using univariate and multivariate analyses.
Results:
477 premenopausal women with breast cancer were identified. Clinicopathologic factors, including age, race, tumor histology, receptor status, and treatment types were well balanced between the two breast density groups. On univariate analysis, breast density did not correlate with stage at presentation, tumor grade, lymphovascular invasion, clinical stage, treatment type, surgery type or overall survival. Lower breast density was strongly correlated with higher BMI, poorer disease free survival (DFS), and larger tumor size on univariate analysis (Table 1). Multivariate analysis also showed that BMI (p = 0.05) and tumor size (p = 0.001) were significantly associated with DFS, whereas breast density was not.
Conclusion:
In this retrospective study of premenopausal women with breast cancer, we found that higher breast density was not associated with higher stage at presentation or with poorer outcomes. This study suggests that higher BMI and tumor size at presentation, although related to breast density, are more predictive of recurrence than breast density in premenopausal patients. Further study is needed to elucidate the link between BMI, breast density and outcome in premenopausal breast cancer.
