Comparing Survival With Breast-Conservation Therapy Or Mastectomy In The Management Of Young Women With Earlystage Breast Cancer

85 Background: Previous studies have shown that young women with breast cancer treated with breast-conservation therapy (BCT) experience higher local recurrence rates. Whether such patients are better treated with mastectomy is unclear. The purpose of this study was to evaluate survival outcomes of young women with early-stage breast cancer treated with BCT or mastectomy using a large, population-based database. Methods: Using the Surveillance, Epidemiology, and End Results (SEER) database, information was obtained for all female patients age 20 to 39 diagnosed with T1-2 N0-1 M0 breast cancer between 1990 and 2007 who underwent either BCT (lumpectomy and radiation treatment) or mastectomy. Multivariable analysis as well as a matched pair analysis were performed to compare overall survival (OS) and cause-specific survival (CSS) of patients undergoing BCT and mastectomy. Results: 14,760 women were identified, of whom 45% received BCT and 55% received mastectomy. Median follow-up was 5.7 years (range: 0.5 to 17.9 years). Multivariable analysis revealed year of diagnosis, age, race/ethnicity, grade, PR status, tumor size, number of lymph nodes positive, and number of lymph nodes examined were independent predictors of OS and CSS while ER status was of borderline significance. After accounting for all patient and tumor characteristics, multivariable analysis found that BCT resulted in similar OS (HR: 0.93; CI: 0.83-1.04; p = 0.16) and CSS (HR: 0.93, CI: 0.83-1.05; p = 0.26) as mastectomy. Matched pair analysis, including 4,644 BCT and mastectomy patients, confirmed no difference in OS or CSS: the 5/10/15-year OS for BCT and mastectomy were 92.5%/83.5%/77.0% and 91.9%/83.6%/79.1%, respectively (p = 0.99) and the 5/10/15-year CSS for BCT and mastectomy were 93.3%/85.5%/79.9% and 92.5%/85.5%/81.9%, respectively (p = 0.88). Conclusions: Young women with early-stage breast cancer have equivalent survival whether treated with BCT or mastectomy. These patients should be counseled appropriately regarding their treatment options, and should not choose a mastectomy based on the assumption of improved survival.