Microbiome and Association With Implant Infections

University of California San Francisco (UCSF)

Status and phase: Enrolling; Phase 2

Conditions: Breast Cancer; Breast Cancer Female; Genetic Predisposition to Disease

Treatments: Drug: Cephalexin

Study type: Interventional

Funder types: Other

Identifiers

NCT05020574

217510

NCI-2021-08985 (Registry Identifier)

Details and patient eligibility

About

The most common tissue expander-related infections are from Staphylococcus and Pseudomonas species. In addition, from breast tissue microbiome studies, Staphylococcus and Pseudomonas show variable abundance across samples. The investigator hypothesizes that participants undergoing mastectomy with high initial abundance of Staphylococcus and/or Pseudomonas are more likely to develop subsequent tissue expander-related infections from these respective organisms.

Full description

PRIMARY OBJECTIVE:

I. To determine the feasibility of breast microbiome sampling using the study techniques

SECONDARY OBJECTIVES:

I. To define the differences in the gut and breast microbiomes between participants undergoing mastectomy with implant-based reconstruction who develop post-operative implant infection and those who do not.

II. To determine the effects of post-operative antibiotics on the gut and breast microbiomes after mastectomy with implant-based reconstruction.

OUTLINE: Participants are randomized to 1 of 2 cohorts.

COHORT A: Participants receive postoperative antibiotics to take for at least 7 days post-operatively.

COHORT B: Participants receive no antibiotics post-operatively in the absence of clinical evidence of infection.

Participants are followed up for 90 days.

Enrollment: 200 estimated patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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200 participants in 2 patient groups

Cohort A: Standard antibiotics

Experimental group

Description:

Receive standard pre-incision antibiotics and 24-hour perioperative antibiotics - Prescribed standard postoperative antibiotics to take for at least 7 days post-operatively

Treatment:

Drug: Cephalexin

Cohort B: No antibiotics

No Intervention group

Description:

Receive standard pre-incision antibiotics and 24-hour perioperative antibiotics - No antibiotics post-operatively, unless patient develops clinical evidence of infection