Factors Predicting Locoregional Recurrence after Wide Local Excision – Experience from a Tertiary Centre

Introduction: Locoregional Recurrence (LR) can still develop after breast conserving surgery despite adequate surgical margins and whole breast radiation, even with a boost to the tumour bed. In this study, we evaluated predictors of LR and examined its effect on survival. Methods: Retrospective review was performed of 713 women diagnosed with breast cancer from 2004 to 2011. Results: Locoregional recurrence developed in 74 women (10.4%) and occurred adjacent to the previous tumour bed in half the instances. Surgical margins (P<0.001), nodal involvement (P=0.002), radiation (P=0.003) and 5 years of hormonal therapy (P<0.001) were independent predictors of LR. While LR had no effect on overall survival in women with DCIS (P=0.756), it was associated with poorer distant recurrence-free and overall survival in women with invasive cancer (P<0.001, HR 114.200, 95% CI 40.630–320.900 and P<0.001, HR 14.210, 95% CI 5.651–35.720 respectively). Radiation and hormonal therapy improved survival, showing an additive effect. Radiation, without hormonal therapy, did not improve recurrence-free survival, both locoregional (P=0.190) and distant (P=0.189), nor overall survival (P=0.236) in node-positive disease. However, radiation conferred survival benefit even when given alone in node-negative disease. Conclusion: The rate of locoregional recurrence after breast conserving surgery was 10.4%. Adequate surgical margins and nodal disease were independently associated with LR and both radiation and hormonal therapy improved survival. Survival benefit was greatest in women who completed both radiation and 5 years of hormonal therapy.