Does cavity margin shaving reduce residual tumor and re‐excision rates? A systematic review

PURPOSE: Cavity shaving (CS) is a surgical technique used in the treatment of breast cancer (BC). It may reduce margin positivity in histologic assessment and consequently reduces re‐ excision rates in breast conserving surgery (BCS). The evidence for this assumption is described in the present review. METHODS: A systematic review of relevant literature in English from January 1999 to April 2019 was conducted. The analysis included studies on CS and its effects on re‐excision rates and margin positivity. We searched PubMed databases for relevant publications. In total, 22 studies were included in the present review. RESULTS: The benefit from CS on re‐excision rates and histologic margin positivity was variable. Out of 22 studies, 17 reported a reduction in both re‐excision rates and histologic margin positivity in margin shaved patients. Four studies could not find a significant reduction of second surgeries and residual tumor rates. One study suggested that CS after BCS was superior to single BCS only in subgroup analysis in IDC tumors. CONCLUSION: CS is a surgical technique that was shown to reduce re‐excision and margin positivity rates in most of the studies. Furthermore, it can be a useful tool to assess specimen margins and detect multifocality.