Close/positive margins after breast-conserving therapy: additional resection or no resection?

Area of Science:

• Surgical Oncology
• Breast Cancer Research
• Pathology

Background:

• Preventing breast cancer recurrence is the primary goal of breast cancer surgery.
• Breast-conserving surgery aims to preserve breast appearance while ensuring oncologic safety.
• Positive surgical margins increase local recurrence risk, even if not apparent during gross examination.

Purpose of the Study:

• To evaluate the significance of positive versus close margins in breast cancer surgery.
• To determine the necessity of re-excision for microscopic tumor foci at the margin.
• To balance oncologic outcomes with cosmetic results and patient satisfaction.

Main Methods:

• Review of retrospective surgical series analyzing local recurrence rates based on margin status.
• Discussion of various techniques to ensure clear margins, including imaging, neoadjuvant therapy, and intraoperative margin assessment.
• Analysis of the distinction between microscopic tumor at the margin and tumor involving the inked margin.

Main Results:

• Positive margins, especially those involving inked tumor, significantly increase local recurrence risk.
• Microscopic tumor foci adjacent to the margin, separated from the primary tumor, may not carry the same risk as grossly positive margins.
• The optimal margin width for reducing local recurrence remains undefined, but a single layer of cells may suffice in some cases.

Conclusions:

• Re-excision is generally warranted for margins inked on tumor, given the risk of uncontrolled disease.
• A microscopic focus of tumor at the margin may not require re-excision, especially with modern adjuvant therapies.
• Clinical judgment integrating tumor size, biology, and adjuvant treatment is essential for managing close or positive margins.