RecruitingClinical trialPENN-Surveillance Markers of Utility for Recurrence After (Neo)Adjuvant Therapy for Breast CancerThis is a single center, prospective cross-sectional study of women who have completed therapy for primary breast cancer within 5 years of diagnosis and are at increased risk for relapse. Patients will undergo screening bone marrow aspirate to test for presence of disseminated tumor cells (DTCs) Patients who harbor DTCs will be offered the opportunity for enrollment into a clinical trial of therapy targeting DTCs to prevent recurrence (separate protocols).