Surgical and Oncologic Impact of Cavity Shave Margins in Breast-Conserving Surgery
In brief
Cavity shave margins cut re-excision rates by two-thirds in breast-conserving surgery
In a cohort of 2,648 women, adding circumferential cavity shave margins reduced the need for a second operation from about 19% to 7%, while cancer recurrence was similar (3.5% vs 5.2%) and not statistically different. The technique eases patient burden and may lower costs, but its effect on long-term cancer control remains unclear.
- Journal
- Annals of surgical oncology (Q1)
- Published
- 19 August 2026
- Study design
- Retrospective cohort
- Evidence level
- Level 3, Low (CEBM 3b)
- Authors
- Hannah Liefeld, Pavitra Attanayake, Steven Lee, Jacob Sypniewski, Brooke Dudick, Gerald P Wright, et al.
- PMID
- 42616326
- DOI
- 10.1245/s10434-026-20433-6
Why clinicians should know about it
- Picked for Breast and Endocrine Surgery (paper of the day, 25 August 2026): Cavity shave margins reduce re‑excision in BCS
Abstract
BACKGROUND: Surgical margin status is a critical determinant of local control in breast-conserving surgery (BCS). Circumferential cavity shave margins (CSM) reduce positive margin rates and re-excisions, but their impact on recurrence remains incompletely defined. METHODS: We conducted a retrospective cohort study of patients undergoing BCS for stage 0-III breast cancer within a single integrated health system between 2017 and 2022. Patients were stratified according to operative technique into those undergoing BCS with circumferential CSM and those undergoing BCS without (non-CSM). The primary oncologic endpoint was recurrence; the secondary outcome was re-excision for a positive margin. Multivariable logistic regression identified factors independently associated with recurrence. RESULTS: A total of 2,648 patients met inclusion criteria, including 1762 (66.5%) treated with non-CSM and 886 (33.5%) with CSM. Adoption of CSM increased progressively over the study period. Re-excision for positive margins was significantly lower in the CSM cohort (7.3% vs. 19.2%, p < 0.001). Overall, 122 relapses (4.6%) were documented. Recurrence was observed in 3.5% of patients undergoing CSM and 5.2% treated with non-CSM, although this difference did not reach statistical significance (p = 0.067). On multivariable analysis, CSM was not independently associated with recurrence, whereas higher clinical stage and omission of radiotherapy remained significant predictors. CONCLUSIONS: Although CSM was not independently associated with recurrence after adjustment, routine CSM substantially reduced re-excision for positive margins. Reducing the need for subsequent surgical procedures may lessen patient burden while improving healthcare utilization and lowering associated costs, supporting CSM as a valuable strategy in contemporary BCS.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.