Margins in Breast-Conserving Surgery After Neoadjuvant Therapy

Area of Science:

• Oncology
• Surgical Oncology
• Breast Cancer Research

Background:

• Determining optimal surgical margin width is crucial for breast-conserving therapy (BCT) following neoadjuvant chemotherapy (NAC).
• The impact of margin width on local recurrence and survival after NAC and BCT remains incompletely understood.

Purpose of the Study:

• To investigate the relationship between surgical margin width and oncologic outcomes after NAC and BCT.
• To evaluate the impact of margin width on local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS).

Main Methods:

• Retrospective analysis of 382 patients with stage I-III breast cancer treated with NAC and BCT (2002-2014).
• Multivariate Cox regression analysis was employed to assess the association between margin width and survival endpoints.
• Analysis included margin status (positive, ≤1 mm, 1.1-2 mm, >2 mm) and patient characteristics including receptor subtypes and pathologic complete response (pCR).

Main Results:

• No significant difference in LRFS, DFS, or OS was observed for margins ≤2 mm versus >2 mm.
• No significant difference in DFS or OS was found for margins ≤1 mm versus >1 mm.
• Hormone receptor-positive (HR+) subtype and pCR were correlated with favorable DFS; node negativity correlated with favorable DFS and OS.

Conclusions:

• Surgical margin width did not demonstrate an association with LRFS, DFS, or OS in patients treated with NAC and BCT.
• Excellent long-term outcomes were observed in patients with close margins (≤2 mm) after NAC.
• A 'no-ink-on-tumor' margin may be considered acceptable for select breast cancer patients undergoing NAC and BCT.