The American Society of Breast Surgeons classification system for oncoplastic breast conserving surgery independently predicts the risk of delayed wound healing

Introduction: Oncoplastic breast conserving surgery (OBCS) aims to provide safe and satisfying surgery for breast cancer patients. The American Society of Breast Surgeons (ASBrS) classification system is based on volumetric displacement cut-offs (level I for <20% of breast volume; level II for 20-50%). It aims to facilitate communication among treating physicians and patients. Here, we investigate whether the extent of OBCS as classified by ASBrS independently predicts postoperative complications.

Materials and methods: This retrospective analysis of a prospectively maintained database included patients with stage I-III breast cancer who underwent OBCS between 03/2011 and 12/2020 at a Swiss university hospital. Outcomes included short-term (≤30 days) complications and chronic (>30 days) pain after surgery. Multivariate logistic regression models were used to identify independent predictors.

Results: In total, 439 patients were included, 314 (71.5%) received ASBrS level I surgery, and 125 (28.5%) underwent ASBrS level II surgery. ASBrS level II was found to be an independent predictor of delayed wound healing (odds ratio [OR] 9.75, 95% confidence intervals (CI) 2.96-32.10). However, ASBrS level did not predict chronic postoperative pain (incidence rate ratio [IRR] 1.20, 95%CI 0.85-1.70), as opposed to age (IRR 1.19, 95%CI 1.11-1.27 per 5 years decrease), and weight disorders (underweight [BMI <18.5] vs. normal weight [BMI 18.5 < 25]: IRR 4.02, 95%CI 1.70-9.54; obese [BMI ≥30] vs. normal weight: IRR 2.07, 95%CI 1.37-3.13).

Conclusion: ASBrS level II surgery predicted delayed wound healing, warranting close clinical follow-up and prompt treatment to avoid delays in adjuvant therapy.