Aesthetic-oriented breast reconstruction: a feasibility study of a novel technique combining Suture-Based Marking Scar Minimising and Axillary-Lateral Thoracic Fat Flap Reconstruction with Tissue Sliding (S-SMARTS)

Breast-conserving surgery with radiotherapy offers outcomes comparable to those of mastectomy. However, margin control and cosmetic results remain challenging, especially for deep or unfavorably located tumors. This study evaluated the S-SMARTS technique (suture-based marking, scar minimizing, and axillary-lateral thoracic fat flap reconstruction with tissue sliding), a hidden-scar, volume displacement method using axillary and lateral thoracic fat flaps. In this single-center retrospective study (Osaka University, Jan 2020-Apr 2025), 44 patients underwent breast-conserving surgery using S-SMARTS. The margin status and cosmetic outcomes (via BCCT.core) were analyzed. Negative margins were achieved in 95.5% of cases on the initial excision and 100% after intraoperative frozen section. The BCCT.core assessment demonstrated that 76.2% of the cases had "Good/Excellent" and 23.8% had "Fair" outcomes. Multivariate analyses were performed to explore any potential predictors of margin positivity. However, no statistically robust predictors were identified. S-SMARTS demonstrates technical feasibility and acceptable early oncologic and aesthetic outcomes in a single-surgeon cohort. Further comparative and multi-institutional studies are warranted to validate its oncologic impact, reproducibility, and patient-reported aesthetic benefits.