PURPOSE: to identify the risk factors associated with the occurrence of surgical site infection (SSI) in surgeries for the treatment of breast cancer. METHODS: the study was conducted on 140 women submitted to treatment of invasive breast cancer during the period from January 2001 to December 2002. SSI was defined as infection occurring up to 30 days after surgery and was related to the operation, according to the standard criteria adopted by the Centers for Disease Control and Prevention (CDC), USA. SSI were considered to be superficial when they involved only the skin and subcutaneous tissue and deep when they involved deep tissues at the site of incision, such as fascia and muscles. The risk factors related to patient were age, hormonal status, staging, body mass index (BMI) and hemoglobin, and the factors related to surgery were type of operation, time of hospitalization, duration of surgery, and formation of seroma and hematoma. Data concerning numerical nonparametric variables were analyzed by the Mann-Whitney test and quantitative variables were analyzed by the Fisher exact test. RESULTS: of the 140 patients studied, 29 (20.7%) presented SSI, which were superficial in 19 (13.6%) and deep in 10 (71%); 111 patients did not present SSI and represented the control group. The risk factors associated with the patient and the disease were locally advanced stage (odds ratio = 27; 95% CI: 1.1-6.5) and obesity, represented by a mean BMI of 32.2 kg/m² in the patients with SSI and a mean BMI of 27.2 kg/m² in the control group (p<0.0001). The factors related to treatment of the disease were the use of neoadjuvant chemotherapy (odds ratio = 2.7 (95% CI: 1.1-6.5), the duration of surgery, whose median value was 165 minutes for the patients who developed the infection and 137 minutes for the control group (p=0.02), and the number of days of use of the postoperative drain, whose median value was 6 days for the patients with SSI and 5 days for the control group (p=0.048). CONCLUSION: on the basis of the identification of risk factors such as advanced stage, neoadjuvant chemotherapy and obesity, preoperative care for these patients should be emphasized. The use of an accurate surgical technique may reduce the impact of other factors such as surgical time and time of use of the drain.
Surgical infections; Breast; Surgery; Obesity; Diabetes mellitus
