44 Long-Term Oncological Outcomes After Oncoplastic Therapeutic Mammoplasty With Contralateral Symmetrisation for Early Breast Cancer: A Thirteen-Year Single-Centre Cohort Study

Background

Long-term oncological outcome data following oncoplastic breast-conserving surgery (OBCS) remain limited. Therapeutic mammoplasty with contralateral symmetrization (TMCS) enables wide local excision with immediate bilateral reshaping, but robust long-term disease control data are needed to support its oncological safety. This study aimed to report long-term disease outcomes following TMCS for early-stage breast cancer at a single high-volume tertiary breast referral center and to identify predictors of local recurrence.

Materials and Methods

A prospective database was established in 2013, including consecutive adult patients undergoing TMCS for early breast cancer. This analysis included unilateral cases of invasive ductal carcinoma or invasive lobular carcinoma without metastatic disease. Updated recurrence, surgical reintervention, and mortality data were obtained from clinical records. Cumulative incidence of local recurrence was estimated using competing-risk methods (competing events: distant metastasis and disease-free mortality) and compared with Kaplan-Meier estimates. Univariable predictors of local recurrence were explored using competing-risk regression.

Results

A total of 133 patients were included. Median age was 56 years (IQR, 50-63), and 64.7% presented symptomatically. Median follow-up was 8.15 years (IQR, 6.35-9.49). Ten-year all-cause mortality was 13% (95% CI, 7.9%-21%). At 10 years, the cumulative incidence of local recurrence was 9.7% (95% CI, 5.0%-16%), distant metastasis was 12% (95% CI, 6.2%-19%), and disease-free mortality was 3.2% (95% CI, 1.1%-7.5%); 75.1% (95% CI, 57.5%-87.7%) remained disease-free. Significant univariable predictors of local recurrence included incomplete radiotherapy (OR, 7.62; 95% CI, 1.52-38.3; P = .014), declined medical treatment (OR, 5.94; 95% CI, 1.86-18.9; P = .003), and estrogen receptor–positive status, which was protective (OR, 0.35; 95% CI, 0.14-0.85; P = .021).

Conclusions

TMCS demonstrated low long-term local recurrence with acceptable distant metastasis and survival outcomes over extended follow-up. The strongest modifiable predictor of recurrence was failure to complete adjuvant therapy, underscoring the importance of treatment adherence in optimizing oncological outcomes following OBCS.