A Randomized, Double-blinded Placebo-controlled Clinical Trial of the Routine Use of Preoperative Antibiotic Prophylaxis in Modified Radical Mastectomy

The effectiveness of antibiotic prophylaxis for prevention of surgical site infection (SSI) following specific types of breast cancer surgery remains uncertain. This study assessed the effectiveness of prophylaxis in modified radical mastectomy (MRM). Women undergoing MRM for breast cancer were recruited. Women were excluded who had diabetes mellitus, severe malnutrition or known allergy to cephalosporins; were receiving corticosteroid therapy or were treated with antibiotics within one week prior to surgery; were scheduled for simultaneous breast reconstruction or bilateral oophorectomy; had existing local infection. Participants were randomized to receive either intravenous cefazolin 1 g or placebo within 30 min prior to skin incision. Standard skin preparation and operative technique for MRM were carried out. Wounds were assessed for SSI and other complications weekly for 30 days. A total of 254 women were recruited. Age, clinical stage, prior chemotherapy, and operative time were similar for antibiotic and placebo groups. The overall incidence of SSI was 14.2 %. There were no significant differences in the infection rate over the 30-day follow-up period between the placebo and antibiotic groups (15 % vs 13.4 %; p = 0.719) or at each week. The majority of SSI were either cellulitis or superficial infection for both groups. There were no significant differences between groups in treatments required for SSI, incidence of hematoma or seroma. The findings of this study, alone and when meta-analyzed with data from studies in similar surgical populations, do not support the use of antibiotic prophylaxis in MRM.