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Updated: Jan 20, 2026

Single-Port Robotic-assisted Transaxillary Breast-conserving Surgery: A Prospective, Single-arm, Non-randomized Phase IIa Clinical Trial
Published on: August 19, 2025
The Impact of Margin Status on Breast Conservation Rates
1Surgical Oncology, University of Nebraska Medical Center, Omaha, USA. esilva@unmc.edu.
Background:
Contemporary data indicate that breast conservation treatment (BCT) results in superior survival outcomes compared with mastectomy. However, positive margins after lumpectomy have implications for local control, and re-excisions are recommended to achieve negative margins. The need for reoperations after an initial attempt at BCT is associated with higher chance of conversion to mastectomy. Achieving negative margins at the first therapeutic surgical procedure is therefore critical to optimise BCT rates and survival outcomes.
Methods:
A compilation of scientific reports on BCT, margin status, rates of reoperation, and the impact on BCT rates was reviewed. Re-excision rates after initial lumpectomy is variable to a staggering degree and reported to be between 0 and 100%. High reoperation rates (ROR) are associated with higher likelihood of conversion to mastectomy, which may not confer favourable treatment outcomes. Although widely agreed that decreasing ROR is a desirable objective, there is controversy regarding the need for its urgent implementation as a quality metric. Critics of this cite challenges related to how this can be achieved and its attendant ramifications. On the other hand, without the appropriate incentive for quality improvement of surgical treatment of breast cancer, patients may be subject to poorer overall outcomes.
Discussion:
Techniques and approaches are discussed in this article to enable a reduction in positive margin status, and therefore ROR. The rationale for achieving ROR of 10-20% are explicated, as well as the impact this would have on BCT rates, which translates to better survival outcomes for women with breast cancer.
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