Inclusion Criteria:  Patients must have histologically confirmed breast malignancy Age >= 18 years Scheduled to undergo mastectomy with the immediate placement of tissue expanders Ability to understand a written informed consent document, and the willingness to sign it At least 4 weeks post-completion of chemotherapy  Exclusion Criteria:  Any significant medical condition or laboratory abnormalities, which places the subject at unacceptable risk if he/she were to participate in the study Pregnant or breastfeeding Patients who have taken antibiotics within 90 days of the consent date Patients who have taken probiotics within 90 days of the consent date Patients who have a documented or reported allergic reaction to the outlined antibiotics to be used in this study Male patients