Background: Younger women with breast cancer have relatively poor prognosis and higher rates of locoregional recurrence. Epidemiologic data suggest equivalent survival with mastectomy or breast conserving surgery (BCS) in this population. We analyzed patterns of care and survival outcomes for women aged < 45 years with breast cancer treated at Ascension Macomb Oakland Hospital (AMOH), Ascension St John Hospital (ASJH), and Ascension Providence Hospital (APH). Methods: Between 2006 and 2015 there were 4703 patients treated for breast cancers at AMOH, ASJH, and APH. We identified a subset of 319 patients aged < 45 treated for breast cancers and investigated patients' tumor characteristics, type of surgery, and overall survival by using the Metric database and reviewing patient charts. Kaplan-Meier analysis and log-rank tests together with univariate analysis was done by using SAS for Windows 9.4. Results: With median follow-up of 53 months among living patients, 26 patients had died. African American race was associated with decreased overall survival (log-rank p=0.0031). Factors associated with improved overall survival included AJCC stage grouping (p=0.009), estrogen receptor (p=0.0004) or progesterone receptor positivity (p=0.005), or HER2 negativity (p=0.039). Similarly, survival was different according to grouping cases as luminal A (n=174), luminal B (n=39), basal (n=46), HER2 (n=23) and unknown phenotype (n=37) (P=0.008). Considering all cases 91 were treated with BCS (28.5%) and 228 with mastectomy (71.4%; 113 unilateral and 115 bilateral with or without reconstruction). Conclusions: In this group of young women, overall survival was influenced by stage and breast cancer phenotype as expected. African American race was associated with inferior overall survival. We found high rates of mastectomy with or without reconstruction. In the future comprehensive disease profiling will help to direct decision making.