Abstract P2-13-13: Predictors of bilateral mastectomy in breast cancer patients

Abstract

Abstract Background: Breast cancer surgery has experienced an evolutional change from radical mastectomy to conservative techniques due to the migration of stage of disease at diagnosis and adjuvant use of multimodality treatment. While breast conservation is preferred by most, the trend of bilateral mastectomy has been on the rise in the United States. The aim of this study is to determine factors that may affect patients’ choice of bilateral mastectomy. Methods: This is a retrospective study of 376 patients diagnosed with primary invasive breast cancer who were treated by bilateral or unilateral mastectomy (BM or UM) at the Revlon/UCLA Breast Center between Jan. 2002 and Dec. 2010. Patients in the bilateral mastectomy (BM) group were further divided into groups of bilateral mastectomy for bilateral breast cancer and for unilateral breast cancer and contralateral prophylactic mastectomy. Results: When compared with the UM group, the following factors were found to be associated with the BM: younger age (p<0.001), pre-menopause (p<0.001), having a family history of breast cancer (p<0.001) or ovarian cancer (p=0.017), BRCA 1 and 2 mutations (p<0.001, p=0.011, respectively), more breast biopsies (p=0.007), history of breast augmentation (p=0.014), more MRI study within 6 months before the surgery (p=0.029), more likely to have reconstruction surgery (p<0.001) and sentinel lymph node biopsy (SLNB) (p<0.001). Multivariate analysis indicated that patients with smaller tumor size (p<0.001, OR 0.087), negative nodes (p<0.001), sentinel lymph node biopsy as nodal surgery (p<0.001, OR 0.259), BRCA mutation (p=0.020, OR 6.537) and positive family history (p=0.001, OR 2.732) were more likely to choose bilateral mastectomy with reconstruction using tissue expanders or implants (p<0.001, OR 4.546). Conclusion: Bilateral mastectomy is associated with lower TN stage, requiring only SNLB, presence of BRCA mutation and/or high risk family history. Tissue expanders or implants based reconstructions were more frequently chosen by patients with bilateral mastectomy. Citation Format: Yun Fu, Zhigang Zhuang, Michelle Dewing, Apple Sophia, Chang R Helena. Predictors of bilateral mastectomy in breast cancer patients [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-13-13.