Are mastectomies on the rise? A 13-year trend analysis of the selection of mastectomy versus breast conservation therapy in 5865 patients.

BACKGROUND: The equivalency of survival between mastectomy and breast conservation therapy (BCT) has long been established, resulting in two decades of predominant BCT. Recently, surgeons have recognized a trend toward increasing mastectomy. Institutional trends of mastectomy and BCT were reviewed, confirming this perception in the surgical treatment of breast cancer. This report evaluates the factors that influence patient decisions to choose surgical therapies.
METHODS: Patients who underwent mastectomy or BCT for invasive and in situ breast cancer were identified upon retrospective review of a prospectively accrued breast cancer database between 1994 and 2007. Univariate and multivariate logistic regression analysis were used to estimate the odds ratio (OR) of the association between mastectomy and patients' clinicopathologic characteristics.
RESULTS: Of the 5,865 patients, 3,736 underwent BCT and 2,129 underwent mastectomy. The overall surgical volume decreased during the study period. Mastectomy rates during the periods of 1994-1998, 1999-2003, and 2004-2007 were 33%, 33%, and 44%, respectively (P < 0.01). Immediate reconstruction rates decreased during the same time periods from 16%, 5%, and 7%, respectively (P < 0.01). On logistic regression analysis, gender, age < 40 years, increase tumor size, and lymphovascular invasion were significant independent predictors of mastectomy. The mastectomy rate increased during the period 1999-2003 (OR 1.2) and during 2004-2007(OR 1.8).
CONCLUSIONS: The perception of an increasing choice toward mastectomy has been confirmed at this institution. Possible reasons are younger population with higher lifetime risk, higher stage disease, and more biologically aggressive or diffuse tumors. Patient preference, fear of genetic or recurrence risk, and "intangible" factors seem to shift decisions toward mastectomy.