Exploring the link between breast microbiome and implant infections after mastectomy

Microbiome and Association With Implant Infections: Investigating the Impact of Antibiotics on the Gut and Breast Microbiomes Post-mastectomy With Implant-based Breast Reconstruction

Phase 2 Interventional University of California, San Francisco · NCT05020574

This study tests if the bacteria in the breast can affect the chances of getting infections after mastectomy and implant surgery, comparing those who get antibiotics with those who don’t.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment200 (estimated)
Ages18 Years and up
SexFemale
SponsorUniversity of California, San Francisco Academic / other
Drugs / interventionschemotherapy, radiation
Locations1 site (San Francisco, California)
Trial IDNCT05020574 on ClinicalTrials.gov

What this trial studies

This study investigates the relationship between the breast microbiome and the risk of implant-related infections in patients undergoing mastectomy with immediate reconstruction. Participants will be randomized into two groups: one receiving postoperative antibiotics and the other receiving no antibiotics unless an infection is clinically evident. The study aims to assess the feasibility of microbiome sampling and to compare the gut and breast microbiomes of those who develop infections versus those who do not. Follow-up will occur over a 90-day period to monitor outcomes.

Who should consider this trial

Good fit: Ideal candidates are adult females with confirmed breast cancer or a genetic predisposition, scheduled for mastectomy with immediate implant placement.

Not a fit: Patients who are male, pregnant, or have taken antibiotics or probiotics recently may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved strategies for preventing infections in breast cancer patients undergoing reconstruction.

How similar studies have performed: While there is ongoing research into the microbiome's role in infections, this specific approach is relatively novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Patients must have histologically confirmed breast malignancy OR genetic predisposition to breast cancer.
2. Age \>= 18 years
3. Scheduled to undergo mastectomy with the immediate placement of tissue expanders or implant placement
4. Ability to understand a written informed consent document, and the willingness to sign it
5. At least 4 weeks post-completion of chemotherapy or radiation therapy.

Exclusion Criteria:

1. Any significant medical condition or laboratory abnormalities, which places the subject at unacceptable risk if he/she were to participate in the study
2. Pregnant or breastfeeding
3. Patients who have taken antibiotics within 90 days of the consent date
4. Patients who have taken probiotics within 90 days of the consent date
5. Patients who have a documented or reported allergic reaction to the outlined antibiotics to be used in this study
6. Male patients

Where this trial is running

San Francisco, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Breast CancerBreast Cancer FemaleGenetic Predisposition to DiseasePost-Surgical AntibioticsBreast Implant InfectionsBreast MicrobiomeBreast ReconstructionMastectomy
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.