Can Radiologic Tumor Size Following Neoadjuvant Therapy Reliably Guide Tissue Resection in Breast Conserving Surgery...

Area of Science:

• Oncology
• Surgical Oncology
• Breast Cancer Research

Background:

• Determining optimal tissue resection volume after neoadjuvant therapy (NAT) for invasive breast cancer is crucial for successful breast-conserving surgery.
• Current guidelines lack definitive recommendations for adjusting resection volumes based on post-NAT imaging findings.

Purpose of the Study:

• To compare positive margin rates and in-breast tumor recurrence (IBTR) between patients undergoing breast-conserving surgery with resection volumes guided by pre-NAT versus post-NAT radiologic tumor size (RTS).

Main Methods:

• Retrospective analysis of 82 patients with 84 breast cancers treated with NAT between 2007-2017, with pre- and post-NAT imaging.
• Patients were divided into two groups: Pre-NAT (resection volume closer to diagnosis RTS) and Post-NAT (resection volume closer to post-NAT RTS).
• Comparison of clinical characteristics, IBTR, and disease-free survival (DFS) between the two groups.

Main Results:

• The Post-NAT group had significantly larger RTS at diagnosis and post-NAT compared to the Pre-NAT group.
• At a median follow-up of 4 years, no significant differences were observed in pathologic tumor size, positive margin rate, adjuvant therapy, IBTR, or DFS between the Pre-NAT and Post-NAT groups.
• Resection volumes aligned with post-NAT RTS did not correlate with increased positive margins or IBTR.

Conclusions:

• Using post-NAT imaging to guide lumpectomy volume in breast cancer patients treated with NAT appears safe and effective.
• This approach does not compromise oncologic outcomes, including margin status and recurrence rates.
• Post-NAT imaging may be a valuable tool for optimizing surgical planning in breast-conserving surgery following neoadjuvant therapy.