Do Patients After Reexcision Due to Involved or Close Margins Have the Same Risk of Local Recurrence as Those After One-Step Breast-Conserving Surgery?

To explore whether patients after a reexcision due to involved or close margins have the same risk of local recurrence (LR) than those after a one-step breast-conserving surgery (BCS); to learn whether the presence of residual cancer in the reexcision specimen influences the probability of LR. We reviewed demographic, clinical, radiologic, and pathologic records of a cohort of women diagnosed with invasive cancer or carcinoma-in situ who underwent BCS surgery as final surgical treatment between January 1, 2003, and December 31, 2011. Univariable and multivariable Cox regression analyses were used to evaluate influencing factors of LR. A total of 2657 patients were eligible for inclusion onto this study. LR was observed in 67 patients (2.5 %) after a median follow-up of 52 months. Reexcision surgery was performed in 486 patients (18.3 %). The 5-year LR-free survival rate was 94.5 % in the reexcision group and 98.0 % in the group with one-step BCS surgery (p < 0.001). In multivariable Cox regression analyses including different covariates patients with a reexcision had a two to eightfold higher risk of LR. Residual cancer in the reexcision specimen did not influence the LR rate (hazard ratio 1.1, p = 0.779). This study suggests the importance of a complete tumor resection ideally within one surgical procedure. Therefore, rigorous preoperative planning, multidisciplinary decision making, and additional intraoperative techniques (e.g., ultrasound, specimen radiography, and/or cavity shaved margin) should be used to avoid the need for reexcision.