Phase IV Study of Determining the Efficacy of Ampicillin/Sulbactam Combination as Antibiotic Prophylaxis During Breast Cancer Surgery in Patients With a Body Mass Index (BMI) Over 25.

CONTEXT Although breast surgery is regarded as clean surgery, the actual SSI rate is well above accepted range in various series. Retrospective studies showed BMI as one of the factors which may have caused increased SSI rate after breast cancer surgery. Yet, no prospective randomized study assessed the efficacy of chemoprophylaxis during breast surgery in overweight patients.

OBJECTIVE To compare the SSI rate between three groups of early stage breast cancer patients in which two are assigned according to randomization. First, patients are grouped into two according to their BMI. All patients (Control Group) with BMI equal to or below 25 do not receive any antibiotics as prophylaxis. Patients with a BMI above 25 are randomly assigned to receive a single dose prophylactic ampicillin /sulbactam combination before surgery (Prophylaxis Group) or not to receive chemoprophylaxis (No Prophylaxis Group).

DESIGN, SETTING AND PATIENTS Patient recruitment is still continuing after the study started in October 2003 in order to reach a sample size of 360 patients with BMI over 25. Advanced or distant metastatic stage, receiving neoadjuvant therapy, history of receiving antibiotics within prior 3 months, history of immunodeficiency, having a remote infection and history of reaction to treatment antibiotics are within the exclusion criteria.

INTERVENTIONS All patients are followed for 30 days postoperatively (once in a week at the original surgical unit). Patients and the investigator who inspects all wounds are blinded. Cost of SSI-related prophylaxis and treatments (including additional hospital visits after discharge, physician charges, additional antibiotics, wound management, other drugs and interventions etc) is calculated in each study group and compared with each other.