1072 – Oncologic and aesthetic outcomes of extreme versus standard oncoplastic breast surgery: a matched cohort study

Abstract

Introduction/Objective: This study compared extreme oncoplasty (EO), defined as partial breast reconstruction for
T3, T4 and/or multicentric tumors, with standard oncoplasty (SO), defined as partial breast reconstruction for unifocal
T1 or T2 tumors.
Methods: This was a retrospective cohort study of 414 women including 138 patients with multicentric or locally advanced
tumors (T3/T4) and 276 patients with early-stage tumors (T1/T2). All underwent breast reconstruction between March
2004 and September 2025. Patients were matched 1:2 by age and date of surgery, with a maximum variation of five years.
Clinical and pathological parameters, complications, local recurrence, survival, and aesthetic outcomes were assessed.
The study was approved by the centers’ ethics committees, and informed consent was obtained from all participants.
Results: The mean follow-up was 44 months for EO and 54 months for SO (p=0.17). Tumor size prior to chemotherapy
was significantly larger in EO (60 mm) compared to SO (25 mm; p<0.01). Neoadjuvant chemotherapy was administered
to 72% of EO patients versus 30% of SO patients. Immediate reconstruction was performed in 89% of both groups. No
significant differences were observed in positive margins, re-excision rates, conversion to mastectomy, or complication
rates. BREAST-Q analysis showed no statistical differences across most parameters, except for nipple satisfaction, which
was higher in the SO group (p<0.01). Harvard scale and BCCT.core software indicated better symmetry in SO. Five-year
overall survival was similar (94.4% EO vs. 98.6% SO; p=0.35), as was locoregional recurrence-free survival (97.0% EO vs.
96.8% SO; p=0.13).
Conclusion: EO surgery achieved oncologic outcomes comparable to SO despite being performed in patients with larger
and more advanced tumors. Aesthetic results were generally similar, although nipple satisfaction and breast symmetry
favored SO. EO may therefore be considered a safe and feasible option for selected patients.
Ethics: Research Ethics Committee Approval, Opinion No. 2.198.758.