Prediction of Local Recurrence After Oncoplastic Breast Surgery: Analysis of a Large Cohort.

ABSTRACT Background Oncoplastic breast surgery (OBS) is becoming an acceptable procedure for the surgical treatment of breast cancer; however, its safety and recurrence rate still need further clarification. This study evaluates the rate of local recurrence and its predictive factors after OBS in a large series of patients. Materials and methods This study was conducted between January 2008 and June 2018 in two centers in Iran. Patients underwent OBS, and baseline characteristics were recorded. Patients underwent regular follow-up; local recurrence rate, median time, and the hazard ratio of predictive factors were calculated. Also, a multivariate analysis was performed. Results A total of 676 patients with a mean age of 48 ± 10.7 y were included. The median follow-up time was 26.4 (first, third IQR: 13.2, 45.6) mo, and 37 (5.5%) patients were diagnosed with local recurrence. The median time to local recurrence was 22.0 (first, third IQR: 16.0, 32.8) mo. Pathological N stage, neoadjuvant chemotherapy, overexpression of HER2, and one surgery technique was associated with a higher risk of recurrence, while the expression of estrogen receptor and progesterone receptor (PR) decreased the risk of recurrence. PR status, neoadjuvant chemotherapy, and pathological N stage remained significant in the final model for recurrence on multivariate analysis. Conclusion OBS is a safe technique with an acceptable risk of local recurrence. PR status, neoadjuvant chemotherapy, and pathological N stage can predict recurrence in these patients with an acceptable power.