Bilateral Mastectomy versus Breast-Conserving Surgery for Early-Stage Breast Cancer: The Role of Breast Reconstruction.

BACKGROUND: Although breast-conserving surgery is oncologically safe for women with early-stage breast cancer, mastectomy rates are increasing. The objective of this study was to examine the role of breast reconstruction in the surgical management of unilateral early-stage breast cancer.
METHODS: A retrospective cohort study of women diagnosed with unilateral early-stage breast cancer (1998 to 2011) identified in the National Cancer Data Base was conducted. Rates of breast-conserving surgery, unilateral and bilateral mastectomy with contralateral prophylactic procedures (per 1000 early-stage breast cancer cases) were measured in relation to breast reconstruction. The association between breast reconstruction and surgical treatment was evaluated using a multinomial logistic regression, controlling for patient and disease characteristics.
RESULTS: A total of 1,856,702 patients were included. Mastectomy rates decreased from 459 to 360 per 1000 from 1998 to 2005 (p < 0.01), increasing to 403 per 1000 in 2011 (p < 0.01). The mastectomy rates rise after 2005 reflects a 14 percent annual increase in contralateral prophylactic mastectomies (p < 0.01), as unilateral mastectomy rates did not change significantly. Each percentage point of increase in reconstruction rates was associated with a 7 percent increase in the probability of contralateral prophylactic mastectomies, with the greatest variation explained by young age(32 percent), breast reconstruction (29 percent), and stage 0 (5 percent).
CONCLUSIONS: Since 2005, an increasing proportion of early-stage breast cancer patients have chosen mastectomy instead of breast-conserving surgery. This trend reflects a shift toward bilateral mastectomy with contralateral prophylactic procedures that may be facilitated by breast reconstruction availability.